Abstract

Temperature diffusivity of laser micro-structured regions in sapphire is determined by a temperature wave method with a lateral resolution reduced to ~ 10 μm using a directly sputtered micro-sensor and heater. A record high reduction of the temperature diffusivity of sapphire by 12% from its (1.26±0.02)×10-5 m2/s in-bulk value inside the femtosecond laser-structured volumes is determined; in a BK7 glass (~ 4.8×10-7 m2/s), a 2% decrease of the thermal diffusivity has been observed. Origin of the reduction is consistent with disorder and scattering of phonons around the laser photo-modified micro-volumes. The stress-induced birefringence is directly measured by polariscopy together with its radial distribution, and azimuthal orientation of the polarization ellipsis near the laser structured regions in sapphire. The maximum birefringence of Δn≃1×10-3 is achieved without crack formation and corresponds to a local stress of ~ 1.3 GPa. The stress (and birefringence) decay radially with a single-exponential constant of τR = 24 μm while the azimuthal orientation of the polarization ellipsis is spiraling around the laser structured volume. Such structures are promising in waveguiding and lasing applications of optical vortices where spatial control of birefringence and optical activity are required.

© 2010 Optical Society of America

1. Introduction

Thermal, mechanical, and optical properties of materials are strongly interrelated and by controlling structural changes on a sub-wavelength scale inside optical materials their mechanical, thermo-electrical, and optical behavior [1–4], relevant to an increasing number of applications in the fields of micro-optics, lab-on-a-chip, optofluidics, waveguiding, and lasing should be better understood. Waveguides directly recorded by laser beam inside plastics [5], optically active and passive glasses [6–9] and crystals [10, 11] are used for sensing, beam splitting/multiplexing, and lasing applications. Birefringent regions formed alongside the laser-recorded micro-structures can also support waveguiding [12, 13]. Recently, a high 1 W output power with good mode quality and 60% conversion efficiency from laser structures in YAG has been reported [14], where the emission is guided in the birefringent region between two inscribed planes inside Nd:YAG crystal.

 

Fig. 1. (a) Al2O3 wafer padded with sputtered Au and Al electrodes used for thermal diffusivity measurements with a close up polariscope view (b) of the laser-structured volume. The sensor (S) and reference (host) positions are marked, respectively. Inset in (b) shows simulated transmission profile according to eqn. 3; the transmission pattern is orientated in the same way as in actual experiments. (c) Schematics of the thermal wave propagation from the heater (on bottom) towards the hot-junction sensor (on top); not to scale. See, the experimental section for details.

Download Full Size | PPT Slide | PDF

For future micro-lasing applications thermal properties of laser crystals and glasses should be well controlled since they are critically important for the long term stability of active micro-optical devices. The thermal properties are dependent on the dopant and defect concentration [15] which affect formation of thermal lensing and might be detrimental for laser operation, especially, at high output power. In the case of the laser inscribed waveguides, the local redistribution of the dopants, laser-induced defects, and even changes of local mass density are all taking place and influence optical functions [16]. A direct measurement of the thermal properties is the required approach [15,17], however, there is lack of techniques allowing direct quantitative measurement of thermal conductivity and diffusivity with a high <1% precision on a micrometer scale. Atomic force microscopy can be used to detect the relative change of thermal properties on a micrometer scale [18], however it is difficult to make such measurement quantitative. The most challenging issue is miniaturization of sensors and thermal contact with sample.

Here, we report on direct measurement of thermal diffusivity by a miniaturized temperature wave (TW) method applied for a high-fidelity characterization of the micro-volumes inside laser-structured sapphire. A record high, up to 12% reduction of thermal diffusivity has been observed in laser structured volumes. The regions just adjacent (~ 3 μm separation) to the ones modified, showed no change of the bulk diffusivity. The stress-induced birefringence near the femtosecond (fs)-laser-structured micro-volumes of tens-of-micrometers in cross section is measured by polariscopy and can amount to Δn ≃ 1×10-3 suitable for waveguide formation. The stress and birefringence show exponential relaxation over length of 24 μm (with the maximum stress estimated to reach 1.3 GPa). The Stokes analysis of birefringence revealed a typical 2π spiraling phase around cylindrical laser-structured volume and could be used for generation of optical vortex.

2. Experimental details

Femtosecond laser pulses 150 fs/800 nm were focused inside samples of sapphire and glass using an objective lens of numerical aperture NA = 1.4 [19]. The irradiation spots were closely packed with typical separations in lateral (x and y) and axial (z) directions: 2×2×1.5 μm. Due to high refractive index of sapphire, n = 1.7 at 800 nm wavelength used for laser structuring, the actual axial period between planes was comparable with the lateral period between void-structures. Also, the regions recorded at larger depth (~ 100 μm) had axially elongated shape due to spherical aberrations [20]. The modified regions were cylindrical with 35 μm in diameter and 90 μm in height to maximize the modified volume within a 126 μm-thick sapphire slab (Shinkoshya Inc.) and BK7 107-μm-thick glass for comparison. Pulse energy used to form void-structures (void with an amorphous shell) in sapphire was 80–120 nJ/pulse at the focus. At these conditions the void of approximately 300 nm in diameter with the amorphous 300-nmshell were formed [21]; in BK7 glass, pulse energies were 60–90 nJ.

The TW method used for high sensitivity measurements of thermal properties of laser host materials [15,17] was adopted for the thermal diffusivity measurements. Typical surface roughness of the thermo-sensors is <100 nm (min-max) after polishing with a 0.1-μm diamond powder. However, such sensor arrays were not suitable for the high precision direct measurements using glass and sapphire with optical grade surfaces due to imperfect thermal contacts at the sensor-sample interface. We sputtered the micro-sensors and heaters for reliable implementation of the TW method which rely on the measurement of the phase delay, Δθ, using lock-in technique [15, 17]:

Δθ=πfχdθ0,

where χ is the thermal diffusivity, f is the repetition rate of the heat wave generation, d is the thickness of sample, and θ0 is the phase accounting for actual experimental conditions and background noise (it has no significance for the experimental determination of χ judged from the slope according to eqn. 1).

The sputtered contacts are chemically stable, have a low electric resistivity and good thermal conductivity: 315 W/mK for Au and 237 W/mK for Al. The thickness of the sputtered Au-Al sensor layer was controlled by monitoring the electric resistance. Typically, sensor of 350-440 Ω was used which does not add up noise to measurements as compared with a thermal noise, V=4kTRΔf, where k is the Boltzmann constant, R is the electrical resistance, and Δf is the bandwidth in herz over which the noise is measured. The sensor was wired via a cold junction with a copper lead. The sensor hot-junctions were simultaneously sputtered on the fabricated, non-fabricated, and adjacent to the laser-structures regions. Precision of the placement of the hot-junctions was approximately 1 μm. Series of up to 10 independent measurements of thermal diffusivity were carried out by chemically removing and resputtering the hot-junction contacts and heater.

A heat source for generation of the temperature wave was a 300-nm-thick layer of Au with an area size of 0.4×1.5 mm2 and is larger than the sensor Au-Al junction. It has an electric resistance of 30 Ω. The larger area assures the one-dimensional heat flow. The heater was wired with a copper lead and the modulated thermal power was chosen to satisfy a good signal-to-noise ratio required for detection of thermal diffusivity changes on the order of < 1%. The temperature jumps were on the order of a few degrees as confirmed by IR thermography and no any changes of structural defects in the laser structured volume occurred.

Polarimetric Stokes analysis was used to determine the birefringence and its spatial distribution around cylindrical micro-structured volumes in sapphire using Abrio IM (Cambridge Research & Instrumentation, Inc.) microscope at 546 nm wavelength [22]. Setup is based on an Olympus BX41 microscope equipped with a UPlanFI 40× objective lens of numerical aperture NA = 1.3.

3. Results and discussion

The direct laser writing by tightly focused femtosecond laser pulses [23, 24] was used to fabricate regions of amorphised sapphire inside crystalline sample at the exactly same conditions as in the previous amorphisation studies [21, 25]. All the samples used in this work were irradiated by tightly focused fs-laser pulses at energy-per-pulse larger than the void formation when the irradiated region has a void surrounded by amorphised shell [19, 26]. Such structural modifications were the focus of this study. Irradiation spots were closely packed to maximize the modified volume.

For this study a micro-scale thermoelectric sensor of Au-Al hot-junctions with a 10×10 μm2 footprint was directly sputtered over the laser-structured regions with a heater sputtered on the opposite side as shown in Fig. 1. This made a perfect surface thermal contact otherwise not possible to achieve with a previous sensor arrangement [27] on high-quality optical surfaces. Next, we analyze the interplay of the thermal, mechanical (stress), and optical (birefringence and optical activity) properties of the laser structured sapphire.

3.1. Thermal diffusivity in micro-volumes

Figure 2 shows normalized thermal diffusivity collected from the regions through the laser-structured, adjacent to it, and at unaffected (host) regions of sapphire sample. Each measurement was carried out after stripping out and re-deposition of contacts and heaters (Fig. 2(a)). Since every single set of sputtered contacts and heaters has slightly different thickness we present data normalized, i.e., the thermal diffusivity of the region S is divided by the value measured at host (see, Fig. 1(b)). The absolute value of thermal diffusivity of host sapphire crystal was determined as (1.28±0.016)×10-5 m2/s at 39°C. A high up to 12% decrease of the thermal diffusivity was observed through the laser structured region repeatedly in separate measurements with overall uncertainty ~1%. Good correspondence of relative changes in thermal diffusivity were observed in repeated measurements. The heat diffusion took place along c-axis (perpendicular to the image plane in Fig. 1(a,b)). Polariscope image show characteristic Maltese cross lobes due to stress-induced birefringence extending laterally up to ~20 μm from the laser-structured regions without crack initiation (Fig. 2(b)).

The region just adjacent to the laser-structured volume has no measurable decrease of thermal diffusivity (3 in Fig. 2). This is the region where stress-induced birefringence is the largest and waveguiding can be realized. Having thermal properties not changed in that particular location is a promising feature for waveguiding and especially lasing applications. The relative changes of thermal diffusivity were reliably measured over 10 cycles (Fig. 2(a)) confirming a high fidelity of the used TW method.

The cause of the decrease in thermal diffusivity is the laser-induced amorphisation and structural modifications around the irradiation spots [26]. The pulse energy was above a threshold of void formation and strong structural modifications occurred around the irradiated volume [19,26]. The thermal diffusivity is defined by the thermal conductivity, kc, the mass density, ρm and the specific heat cp at constant pressure as χ = kc/(ρmcp) and was directly measured in our experiments. The thermal conductivity, kc, is given by [28]:

kc=ρcpvΛ/3,

where v is the mean velocity of the thermal carriers phonons and electrons, ρ is the density of the carriers, and Λ = is the mean free path of the carriers defined via the thermal velocity v and average time interval between scattering events, τ. When dimensions of objects become smaller than Λ, which is typically several tens of nanometers, scattering increases, and τ is reduced, causing smaller Λ and kc. Because of these effects, objects with nanoscale-volumes can efficiently localize heat as was demonstrated by polymerization [29]. Such a large 12% modification of thermal property on the scale of several micrometers can be used for the temperature localization at required location which can be freely three-dimensionally recorded inside bulk of transparent host crystal.

 

Fig. 2. (a) Normalized thermal diffusivity, χShost, (see, Fig. 1(b)) through the laser-structured (1), adjacent (3) regions vs number of measurement cycles. Error bars are 2%. (b) Polariscope image shows a region laser-structured by 80 nJ/pulse energy with two pulse per irradiation site. An approximate location and size of the hot-junction sensors are marked. Inset shows a slanted view of the computer generated 3D pattern of the irradiation spots (circles) and the movement path (lines).

Download Full Size | PPT Slide | PDF

The same thermal analysis has been carried out for BK7 glass and the thermal diffusivity value of (4.81±0.027)×10-7 m2/s (at 45°C) has been determined for the host matrix as expected [30]. A reduction of thermal diffusivity up to 2% in the fs-laser structured regions is observed which is considerably less than in crystalline sapphire. Since BK7 is amorphous the decrease of thermal conductivity might be caused by structural changes in ring-like structures of SiO4 tetrahedrons which occur due to densification of glasses [8, 18, 31].

3.2. Birefringence and azimuthal phase

The stress-induced birefringence was measured by polariscopy using a phase compensation technique for the changes caused by stress-induced birefringence [22]. The intensity of the transmitted light through an optically-crossed polarizer and analyzer with a birefringent material in between is given by [32]:

It(φ,Δn)=I0sin2(2φ)sin2(Γ/2)

where φ is the angle of the polarizer axis with the principal stress direction in the sample, Δn is the induced birefringence, d is the axial extension of the region, and λ0 is the wavelength of light in vacuum, and Γ/2 =πΔnd/λ0 is the retardance. Equation 3 represents the well known Maltese cross intensity distribution (illustrated in the inset of Fig. 1(b)), where the principle directions of stress coincide with the dark lines and points (φ = 0), called isoclinic, in the polarization micrograph. The brightest regions are at φ = π/4 angles. By performing Stokes analysis the birefringence, Δn, and the azimuth, Ψ, or the angular distribution of an optical slow axis can be retrieved for the each pixel of a microscope image, e.g., the Stokes parameter s3 is related to the retardance via s3 = −cosΓ [33].

 

Fig. 3. Polariscopy data. (a) The amplitude, i.e., retardance distribution (Γ(x,y)/2π×λ0) [nm] on a c-plane of sapphire sample with a fs-laser structured region of 30 μm in diameter at the center (as shown in Fig. 2(b)). (b) The azimuth or distribution of the slow axis orientation, Ψ(x,y). The arrows are pointing to location of a pair of topological phase defects where birefringence and the orientation of the polarization ellipsis are undefined. Scale, radians. (c) Horizontal and diagonal cross-sections of the birefringence, Δn(x, y), map given in (a); calculated from experimentally measured retardance Γ(x, y)/2 = πλ0 Δn(x,y)d (λ0 = 546 nm, d ≃ 90 μm). The exponential 1/e fits with a birefringence (stress) relaxation constant τR = 24 μm are shown as eye guides. Red and grey marked regions indicate the laser structured locations. Pulse energy was 80 nJ/pulse. Stress-induced crack formation is demonstrated at the corners of volume with a square footprint (Media 1); this proves a stress-related origin of the birefringence rather than form-birefringence.

Download Full Size | PPT Slide | PDF

Results of the imaging polariscopy analysis are summarized in Fig. 3 for the amplitude (a) and azimuth (b). The amplitude is the retardance presented in nanometers (Γ(x,y)/2π×λ0) [nm] and the azimuth shows slow axis orientation [22].

First, we discuss modifications observed outside the cylindrical fs-laser structured regions (see, Fig. 2(b)). The birefringence with maximum of Δn ≃ 1×10-3 is determined before onset of micro-crack formation for the laser-structured volume used in our experiments. The typical distance over which the birefringence (and stress) relaxed single-exponentially was τR =24 μm (c). The slow axis orientation, the azimuth [22], has radially and azimuthally varying distribution shown by dial-markers in more details in Fig. 4. The azimuthal phase retardation over one full turn around the cylindrical laser structured region of 90 μm length and 30 μm diameter was ~ 2π as revealed by two gradient lobes with a change over π each. Hence, a light waveguided around such laser structured volume in the region of high birefringence would acquire an orbital angular momentum. By recording cylindrical structure inside sapphire the local orientation of optical axis and birefringence can be controlled.

The polariscopic analysis inside the laser structured volume is only qualitative for birefringence since a strong light scattering, as observed in earlier Raman studies [34], causes depolarization of light (boxed regions in Fig. 3(c)). Stress-induced birefringence can be measured with few micron resolution using polariscopy [31]. The two dark regions inside the laser structured volume marked by arrows in Fig. 3 represent topological defects where the orientation of polarization ellipsis is undefined or has a singularity [35] (also, marked in Fig. 4). The location of the phase defects is related to the stress distribution, which is defined by the crystalline orientation of the sample, its thickness, geometry of the recorded pattern, and most probably to the shape of voids and amorphous regions (see Media 1 online file for details). Such singularities are common in different fields of physics and optics [36–40], e.g., pipe-dislocations in GaN crystals [41] and disclinations in liquid crystal films [42]. The disclinations of the director in liquid crystals equivalent to the orientation shown in Fig. 4(b) are defined by the strength parameter s=+1/2. The azimuth of optical axis around each of two singularity points (Fig. 4(b)) is increasing anti-clockwise and in a full turn acquires a cumulative π phase change.

The stress-induced birefringence can be used to generate optical vortex [43] as demonstrated for the macroscopic stressed glass waveplate. The optical vortex is characterized by the azimuthal phase which is changing as exp(ilψ), where ψ is the local azimuthal angle and l is an integer number, the topological charge. The laser-structured volumes create birefringence and a smooth continuous change of azimuthal orientation of the optical axis, hence, such structure would generate optical vortex from a micro-volume in contrast to a large optical element [43]. Alternatively, the micro-optical elements with space-varying birefringence can be recorded in an optically isotropic micro-volume of sapphire (or other material) and the micro-workpiece can then be released by wet-etching [25] for laser trapping applications. Once a micro-particle has birefringence and refractive index is larger than that of surrounding, it can be laser-trapped and spined [44–46], thus, performing pump, sorting, or other mechanical functions in optofluidic applications.

Since the charge, l, of an optical vortex is related to a particular 3D geometry of a spatially-variant birefringence and readout beam (a focusing angle) [47, 48], one would expect that by choosing other shapes of laser-structured micro-volumes one could obtain singularities of different topological charges. At the singularity location a minimum of light intensity is obtained and it is well localized. This has number of potential applications in physics and optics [36–40, 49].

We have chosen to record structure by laser structuring along c-axis, the direction for which sapphire has no birefringence, and to explore stress-induced birefringence and its spatial and azimuthal distribution. Crystal parameters such as photoelastic constants (discussed in next section) related to the Stokes parameters and the bulk modulus govern a birefringence change, its azimuthal distribution, handedness, and optical activity. It would be necessary to explore next, how by changing particular micro-pattern recorded inside bulk of crystal or glass, one could tailor the required changes of birefringence, handedness, optical activity using direct femtosecond laser writing. Such patterns could be used to form vortex beams which carry an orbital angular momentum due to stress-induced spatially variant birefringence around or inside regions specially tailored by laser fabrication. It might have applications in optofluidics, design of micro-optical elements, and laser trapping [50, 51].

3.3. Determination of stress

Let us determine the stress responsible for birefringence of Δn≃10-3. The refractive index of a crystal is related to stress, σ, through the stress-optic (piezo-optic) tensor qij or to strain through the strain-optic (elasto-optic or photoelastic) tensor pij; in the Voigt nomenclature elements of tensors are interrelated pij = qijcij with cij being the stiffness tensor [52]. Strain (ε) is related to stress (σ) through the compliance tensor, sij, and vice versa. The Hook’s law defines a stressto-strain relation via stiffness σi = cijεj [53].

The stress-induced birefringence Δn = n - nn032 where n0 is the average refractive index, n and n are the refractive indices for light with its electric vector parallel and perpendicular to the direction of stress, respectively. The pij [54, 55] and cij [56] values of sapphire were used for calculation of the stress-induced birefringence. In the employed imaging geometry along c-axis (Fig. 1(b)) the stress component, σ3, can be estimated assuming transversely isotropic conditions with symmetry axis along e3 as σ3 = c13ε1+c13ε2+c33ε3 ≃(2c13+c33)ε. We used sapphire constants c13 = 117.2 GPa, c33 = 501.8 GPa [56], p13 = 0.005, p33 = 0.23 [55] for evaluation of effective coefficient q33. It is noteworthy that when the recorded pattern inside sapphire exert a complex 3D stress pattern this proposed estimation can only be used for a qualitative measure since the model is valid for the patterns which are 2D and when their cross sections are considerably larger than the wavelength of light. One would find that a σ3 = 2Δn/(n30q33) ≃ 125 MPa stress is required for the Δn = 1×10-4 birefringence when an average refractive is n0 = 1.7. This is one of the highest photoelastic sensitivities among crystals which is caused by the high p33/p13 ratio as first reported in ref. [57]: an experimentally validated value of Δn = 1×10-4 birefringence was obtained for the 1 kbar (0.1 GPa) hydrostatic pressure.

 

Fig. 4. (a) The azimuth, Ψ(x, y), (grey scale map 0-π) map around two regions of smaller Δnmax ≃ 10-3) (1) and by 50% larger (2) birefringence; the dial-markers shows the orientation of the azimuth; pulse energies were 80 (1) and 120 nJ/pulse (2), respectively. The central laser structured regions have the same 30 μm diameters (marked by circles). (b) Close up view of the central part of region (1) with two singularities of azimuthal orientation of the polarization ellipsis. A round trip phase changes by π for the two singularities (marked by arrows).

Download Full Size | PPT Slide | PDF

The experimentally measured birefringence of 10-3 corresponds to the stress of ~ 1.3 GPa for the employed geometry of laser structuring along c-axis. Since sapphire has the Young modulus of 400 GPa, pressures up to 1 GPa can be created by fs-laser structuring without crack formation [58] and can be used for waveguiding.

4. Conclusions

It has been established that the thermal diffusivity of fs-laser structured micro-volumes in sapphire is reduced by 12% as compared with the host crystalline matrix. Such large change of thermal property can be localized with several micrometers precision inside the bulk of crystalline host. Due to high crack propagation resistance [58] (mainly determined by a high value of Young modulus ~ 400 GPa) the crack-free regions of birefringence up to Δn ≃ 1×10-3 can be formed adjacent to the laser-structured volume and spanning tens of microns. This opens a possibility to form 3D waveguides inside sapphire, ruby (Cr-doped sapphire [59]), and other laser crystals which have comparable mechanical properties and can be used for formation of active lasing waveguiding structures. Thermal diffusivity in the stress-birefringent regions was found unchanged.

Polariscopy imaging is used to quantify the stress-induced birefringence around laser-structured volumes. The peak birefringence of Δn≃10-3 at the edge of laser structured volume is decaying exponentially with spatial constant τr = 24 μm. It is found that azimuth of slow axis is spinning around the laser structured region. This opens possibility to engineer and tailor optical activity and record functional polarization-sensitive micro-devices, e.g., for generating optical vortex beams.

The quantitative measurement of birefringence is used to estimate the stress. The cylindrical volume composed of void-structures exerted a 2D stress pattern. This simplified calculations and the following correspondence has been established: Δn ≃ 10-3 is equivalent to 1.3 GPa stress.

Presented combined assessment of optical, mechanical, and thermal properties inside and around laser structured regions in sapphire should help for miniaturization of optically active and passive functional micro-devices, polarization micro-optics, and can be applied to other crystalline materials and glasses.

Acknowledgments

Support via a Discovery ARC Grant DP0988054, Grant-in-Aid from the Ministry of Education, Science, Sports, and Culture of Japan No. 19360322, and a grant from Japan Science and Technology Agency (Development of System and Technology for Advanced Measurement and Analysis) are gratefully acknowledged. Authors would like to thank Etienne Brasselet for useful discussions, and Tokyo Instruments, Inc. for agreement to publish data obtained by Abrio IM microscope.

References and links

1. M. Ams, G. D. Marshall, P. Dekker, J. A. Piper, and M. J. Withford, “Ultrafast laser written active devices,” Laser Photon. Rev. 3, 535–544 (2009). [CrossRef]  

2. S. K. Sundaram and E. Mazur, “Inducing and probing non-thermal transitions in semiconductors using femtosecond laser pulses,” Nature Mat. 1, 217–224 (2002). [CrossRef]  

3. Y. Lan, A. J. Minnich, G. Chen, and Z. Ren, “Enhancement of thermoelectric figure-of-merit by a bulk nanostructuring approach,” Adv. Func. Mat. , 20, 357–376 (2010). [CrossRef]  

4. S. Juodkazis, V. Mizeikis, and H. Misawa, “Three-dimensional microfabrication of materials by femtosecond lasers for photonics applications,” J. Appl. Phys. 106, 051101 (2009). [CrossRef]  

5. S. Sowa, W. Watanabe, T. Tamaki, J. Nishii, and K. Itoh, “Symmetric waveguides in poly(methyl methacrylate) fabricated by femtosecond laser pulses,” Opt. Express 14, 291–297 (2006). [CrossRef]   [PubMed]  

6. S. Nolte, M. Will, J. Burghoff, and A. Tünnermann, “Femtosecond waveguide writing: a new avenue to three-dimensional integrated optics,” Appl. Phys. A 77, 109–111 (2003). [CrossRef]  

7. L. Shah, A. Arai, S. Eaton, and P Herman, “Waveguide writing in fused silica with a femtosecond fiber laser at 522 nm and 1 MHz repetition rate,” Opt. Express 13, 1999–2006 (2005). [CrossRef]   [PubMed]  

8. D. M. Krol, “Femtosecond laser modification of glass,” J. Non-Cryst. Sol. 354, 416–424 (2009). [CrossRef]  

9. G. Cerullo, R. Osellame, S. Taccheo, M. Marangoni, D. Polli, R. Ramponi, P. Laporta, and S. D. Silvestri, “Femtosecond micromachining of symmetric waveguides at 1.5μm by astigmatic beam focusing,” Opt. Lett. 27, 1938–1940 (2002). [CrossRef]  

10. J. Siebenmorgen, K. Petermann, G. Huber, K. Rademaker, and S. N. A. Tünnermann, “Femtosecond laser written stress-induced Nd:Y3Al5O12(Nd:YAG) channel waveguide laser,” Appl. Phys. B 97, 251–255 (2009). [CrossRef]  

11. A. Benayas, D. Jaque, B. McMillen, and K. P. Chen, “High repetition rate UV ultrafast laser inscription of buried channel waveguides in sapphire: Fabrication and fluorescence imaging via ruby R lines,” Opt. Express 17, 10076–10081 (2009). [CrossRef]   [PubMed]  

12. Z. Zhu and T. G. Brown, “Stress-induced birefringence in microstructured optical fibers,” Opt. Lett. 28, 2306–2308 (2003). [CrossRef]   [PubMed]  

13. G. Cheng, K. Mishchik, C. Mauclair, E. Audouard, and R. Stoian, “Ultrafast laser photoinscription of polarization sensitive devices in bulk silica glass,” Opt. Express 17, 9515–9525 (2009). [CrossRef]   [PubMed]  

14. J. Siebenmorgen, T. Calmano, O. Hellmig, K. Petermann, and G. Huber, “Efficient femtosecond laser written Nd:YAG channel waveguide laser with an output power of more than 1 W,”, Technical Digest, CLEO/Europe-EQEC Conference, 2009, paper CJ7.1.

15. J. Morikawa, C. Leong, T. Hashimoto, T. Ogawa, Y. Urata, S. Wada, M. Higuchi, and J.-I. Takahashi, “Thermal conductivity/diffusivity of Nd3+ doped GdVO4, YVO4, LuVO4,and Y3Al5O12 by temperature wave analysis,” J. Appl. Phys. 103, 063522 (2008). [CrossRef]  

16. S. M. Eaton, H. Zhang, M. L. Ng, J. Z. Li, W. J. Chen, S. Ho, and P. R. Herman, “Transition from thermal diffusion to heat accumulation in high repetition rate femtosecond laser writing of buried optical waveguides,” Opt. Express 16, 9443–9458 (2008). [CrossRef]   [PubMed]  

17. J. Morikawa and T. Hashimoto, “Thermal diffusivity of aromatic polyimide thin films by temperature wave analysis,” J. Appl. Phys. 105, 113506 (2009). [CrossRef]  

18. Y. Bellouard, M. Dugan, A. A. Said, and P. Bado, “Thermal conductivity contrast measurement of fused silica exposed to low-energy femtosecond laser pulses,” Appl. Phys. Lett. 89, 161911 (2006). [CrossRef]  

19. T. Hashimoto, S. Juodkazis, and H. Misawa, “Void recording in silica,” Appl. Phys. A 83, 337–340 (2006). [CrossRef]  

20. A. Marcinkevicius, V. Mizeikis, S. Juodkazis, S. Matsuo, and H. Misawa, “Effect of refractive index-mismatch on laser microfabrication in silica glass,” Appl. Phys. A. 76, 257–260 (2003). [CrossRef]  

21. E. E. Gamaly, S. Juodkazis, K. Nishimura, H. Misawa, B. Luther-Davies, L. Hallo, P. Nicolai, and V. Tikhonchuk, “Laser-matter interaction in a bulk of a transparent solid: confined micro-explosion and void formation,” Phys. Rev. B 73, 214101 (2006). [CrossRef]  

22. M. Shribak and R. Oldenbourg, “Techniques for fast and sensitive measurements of two-dimensional birefringence distributions,” Appl. Opt. 42, 3009–3017 (2003). [CrossRef]   [PubMed]  

23. E. Vanagas, I. Kudryashov, D. Tuzhilin, S. Juodkazis, S. Matsuo, and H. Misawa, “Surface nanostructuring of borosilicate glass by femtosecond nJ energy pulses,” Appl. Phys. Lett. 82, 2901–2903 (2003). [CrossRef]  

24. S. Juodkazis, K. Yamasaki, V. Mizeikis, S. Matsuo, and H. Misawa, “Formation of embedded patterns in glasses using femtosecond irradiation,” Appl. Phys. A 79, 1549–1553 (2004). [CrossRef]  

25. S. Juodkazis, K. Nishimura, H. Misawa, T. Ebisui, R. Waki, S. Matsuo, and T. Okada, “Control over the state of crystallinity: Sapphire,” Adv. Mat. 18, 1361–1364 (2006). [CrossRef]  

26. S. Juodkazis, K. Nishimura, S. Tanaka, H. Misawa, E. E. Gamaly, B. Luther-Davies, L. Hallo, P. Nicolai, and V. Tikhonchuk, “Laser-induced microexplosion confined in the bulk of a sapphire crystal: Evidence of multimegabar pressures,” Phys. Rev. Lett. 96, 166101 (2006). [CrossRef]   [PubMed]  

27. J. Morikawa, A. Orie, T. Hashimoto, and S. Juodkazis, “Thermal diffusivity in femtosecond-laser-structured micro-volumes of polymers,” Appl. Phys. A. 98, 551–556 (2010). [CrossRef]  

28. B. Rogers, S. Pennathur, and J. Adams, Nanotechnology: understanding small systems (CRC Press Taylor and Francis Group, Boca Raton, 2008).

29. K. Ueno, S. Juodkazis, T. Shibuya, V. Mizeikis, Y. Yokota, and H. Misawa, “Nano-particle-enhanced photo-polymerization,” J. Phys. Chem. C 113, 11720–11724 (2009). [CrossRef]  

30. M. J. Assael, K. D. Antoniadis, and J. Wu, “New measurements of the thermal conductivity of PMMA, BK7, and Pyrex 7740 up to 450K,” Int. J. Thermophys. 292, 1257–1266 (2008). [CrossRef]  

31. Y. Bellouard, T. Colomb, C. Depeursinge, M. Dugan, A. A. Said, and P. Bado, “Nanoindentation and birefringence measurements on fused silica specimen exposed to low-energy femtosecond pulses,” Opt. Express 14, 8360–8366 (2006). [CrossRef]   [PubMed]  

32. H. Aben, Photoelasticity of glass (Springer-Verlag Berlin, 1993).

33. E. Brasselet, N. Murazawa, H. Misawa, and S. Juodkazis, “Optical vortices from liquid crystal droplets,” Phys. Rev. Lett. 103, 103903 (2009). [CrossRef]   [PubMed]  

34. V. Mizeikis, S. Kimura, N. V. Surovtsev, V. Jarutis, A. Saito, H. Misawa, and S. Juodkazis, “Formation of amorphous sapphire by a femtosecond-pulse-induced micro-explosion,” Appl. Surf. Sci. 255, 9745–9749 (2009). [CrossRef]  

35. L. Allen, M. J. Padgett, and M. Babiker, “The orbital angular momentum of light,” Progress in Optics 39, 291–372 (1999). [CrossRef]  

36. M. Berry, “Making waves in physics,” Nature 403, 21 (2000). [CrossRef]   [PubMed]  

37. K. T. Gahagan and G. A. Swartzlander, “Optical vortex trapping of particles,” Opt. Lett. 21, 827–829 (1996). [CrossRef]   [PubMed]  

38. M. Harris, C. A. Hill, P. R. Tapster, and J. M. Vaughan, “Laser modes with helical wave fronts,” Phys. Rev. A 49, 3119–3122 (1994). [CrossRef]   [PubMed]  

39. G. Foo, D. M. Palacios, and G. A. Swartzlander, “Optical vortex coronagraph,” Opt. Lett. 30, 3308–3310 (2005). [CrossRef]  

40. H. He, M. E. J. Friese, N. R. Heckenberg, and H. Rubinsztein-Dunlop, “Direct observation of transfer of angular-momentum to absorptive particles from a laser-beam with a phase singularity,” Phys. Rev. Lett. 75, 826–829 (1995). [CrossRef]   [PubMed]  

41. P. G. Eliseev, S. Juodkazis, T. Sugahara, H.-B. Sun, S. Matsuo, S. Sakai, and H. Misawa, “GaN surface ablation by fs-pulses: atomic force microscopy studies, accumulation effects,” in Proceedings of High-Power Laser Ablation Conf. (SPIE Proc. 4065, 2000) pp.546–556.

42. R. A. L. Jones, Soft Condensed Matter (Oxford University Press, 2002).

43. A. K. Spilman and T. G. Brown, “Stress birefringent, space-variant wave plates for vortex illumination,” Appl. Optics 46, 61–66 (2007). [CrossRef]  

44. M. E. J. Friese, T. A. Nieminen, N. R. Heckenberg, and H. Rubinsztein-Dunlop, “Optical alignment and spinning of laser-trapped microscopic particles,” Nature 394, 348–350 (1998). [CrossRef]  

45. S. Juodkazis, M. Shikata, T. Takahashi, S. Matsuo, and H. Misawa, “Fast optical swithing by a laser manipulated microdroplet of liquid crystal,” Appl. Phys. Lett. 74, 3627–3629 (1999). [CrossRef]  

46. S. Juodkazis, S. Matsuo, N. Murazawa, I. Hasegawa, and H. Misawa, “High-efficiency optical transfer of torque to a nematic liquid crystal,” Appl. Phys. Lett. 82, 4657–4659 (2003). [CrossRef]  

47. E. Brasselet, Y. Izdebskaya, V. Shvedov, A. S. Desyatnikov, W. Krolikowski, and Y. S. Kivshar, “Dynamics of optical spin-orbit coupling in uniaxial crystals,” Opt. Lett. 34, 1021–1023 (2009). [CrossRef]   [PubMed]  

48. A. Ciattoni, G. Cincotti, and C. Palma, “Angular momentum dynamics of a paraxial beam in a uniaxial crystal,” Phys. Rev. E 67, 036618 (2003). [CrossRef]  

49. L. Marrucci, C. Manzo, and D. Paparo, “Optical spin-to-orbital angular momentum conversion in inhomogeneous anisotropic media,” Phys. Rev. Lett. 96, 163905 (2006). [CrossRef]   [PubMed]  

50. N. B. Simpson, K. Dholakia, L. Allen, and M. J. Padgett, “Mechanical equivalence of spin and orbital angular momentum of light: An optical spanner,” Opt. Lett. 22, 52–54 (1997). [CrossRef]   [PubMed]  

51. H. Misawa and S. Juodkazis, “Photophysics and photochemistry of a laser manipulated microparticle,” Prog. Polym. Sci. 24, 665–697 (1999). [CrossRef]  

52. P. A. Williams, A. H. Rose, K. S. Lee, D. C. Conrad, G. W. Day, and P. D. Hale, “Optical, thermo-optic, electro-optic, and photoelastic properties of bismuth germanate ABi4Ge3O12B,” Appl. Opt. 35, 3562–3569 (1996). [CrossRef]   [PubMed]  

53. http://en.wikipedia.org/wiki/Hooke’s_law.”

54. J. W. Kysar, “Path of light in near crack tip region in anisotropic medium and under mixed-mode loading,” Int. J. Sol. Struct. 38, 5963–5973 (2001). [CrossRef]  

55. J. Reintjes and M. B. Schulz, “Photoelastic constants of selected ultrasonic delay-line crystals,” J. Appl. Phys. 39, 5254–5258 (1968). [CrossRef]  

56. J. M. Winey, Y. M. Gupta, and D. E. Hare, “r-axis sound speed and elastic properties of sapphire single crystals,” J. Appl. Phys. 90, 3109–3111 (2001). [CrossRef]  

57. T. A. Davis and K. Vedam, “Photoelastic properties of sapphire (α - Al2O3),” J. Appl. Phys. 38, 4556–4557 (1967).

58. M. Beresna, T. Gertus, R. Tomasiunas, H. Misawa, and S. Juodkazis, “Three-dimensional modeling of the heat-affected zone in laser machining applications,” Laser Chemistry 2008, 976205 (2008). [CrossRef]  

59. K. Syassen, “Ruby under pressure,” High Pressure Research 28, 75–126 (2008). [CrossRef]  

References

  • View by:
  • |
  • |
  • |

  1. M. Ams, G. D. Marshall, P. Dekker, J. A. Piper, and M. J. Withford, “Ultrafast laser written active devices,” Laser Photon. Rev. 3, 535–544 (2009).
    [CrossRef]
  2. S. K. Sundaram and E. Mazur, “Inducing and probing non-thermal transitions in semiconductors using femtosecond laser pulses,” Nature Mat. 1, 217–224 (2002).
    [CrossRef]
  3. Y. Lan, A. J. Minnich, G. Chen, and Z. Ren, “Enhancement of thermoelectric figure-of-merit by a bulk nanostructuring approach,” Adv. Func. Mat.,  20, 357–376 (2010).
    [CrossRef]
  4. S. Juodkazis, V. Mizeikis, and H. Misawa, “Three-dimensional microfabrication of materials by femtosecond lasers for photonics applications,” J. Appl. Phys. 106, 051101 (2009).
    [CrossRef]
  5. S. Sowa, W. Watanabe, T. Tamaki, J. Nishii, and K. Itoh, “Symmetric waveguides in poly(methyl methacrylate) fabricated by femtosecond laser pulses,” Opt. Express 14, 291–297 (2006).
    [CrossRef] [PubMed]
  6. S. Nolte, M. Will, J. Burghoff, and A. Tünnermann, “Femtosecond waveguide writing: a new avenue to three-dimensional integrated optics,” Appl. Phys. A 77, 109–111 (2003).
    [CrossRef]
  7. L. Shah, A. Arai, S. Eaton, and P Herman, “Waveguide writing in fused silica with a femtosecond fiber laser at 522 nm and 1 MHz repetition rate,” Opt. Express 13, 1999–2006 (2005).
    [CrossRef] [PubMed]
  8. D. M. Krol, “Femtosecond laser modification of glass,” J. Non-Cryst. Sol. 354, 416–424 (2009).
    [CrossRef]
  9. G. Cerullo, R. Osellame, S. Taccheo, M. Marangoni, D. Polli, R. Ramponi, P. Laporta, and S. D. Silvestri, “Femtosecond micromachining of symmetric waveguides at 1.5μm by astigmatic beam focusing,” Opt. Lett. 27, 1938–1940 (2002).
    [CrossRef]
  10. J. Siebenmorgen, K. Petermann, G. Huber, K. Rademaker, and S. N. A. Tünnermann, “Femtosecond laser written stress-induced Nd:Y3Al5O12(Nd:YAG) channel waveguide laser,” Appl. Phys. B 97, 251–255 (2009).
    [CrossRef]
  11. A. Benayas, D. Jaque, B. McMillen, and K. P. Chen, “High repetition rate UV ultrafast laser inscription of buried channel waveguides in sapphire: Fabrication and fluorescence imaging via ruby R lines,” Opt. Express 17, 10076–10081 (2009).
    [CrossRef] [PubMed]
  12. Z. Zhu and T. G. Brown, “Stress-induced birefringence in microstructured optical fibers,” Opt. Lett. 28, 2306–2308 (2003).
    [CrossRef] [PubMed]
  13. G. Cheng, K. Mishchik, C. Mauclair, E. Audouard, and R. Stoian, “Ultrafast laser photoinscription of polarization sensitive devices in bulk silica glass,” Opt. Express 17, 9515–9525 (2009).
    [CrossRef] [PubMed]
  14. J. Siebenmorgen, T. Calmano, O. Hellmig, K. Petermann, and G. Huber, “Efficient femtosecond laser written Nd:YAG channel waveguide laser with an output power of more than 1 W,”, Technical Digest, CLEO/Europe-EQEC Conference, 2009, paper CJ7.1.
  15. J. Morikawa, C. Leong, T. Hashimoto, T. Ogawa, Y. Urata, S. Wada, M. Higuchi, and J.-I. Takahashi, “Thermal conductivity/diffusivity of Nd3+ doped GdVO4, YVO4, LuVO4,and Y3Al5O12 by temperature wave analysis,” J. Appl. Phys. 103, 063522 (2008).
    [CrossRef]
  16. S. M. Eaton, H. Zhang, M. L. Ng, J. Z. Li, W. J. Chen, S. Ho, and P. R. Herman, “Transition from thermal diffusion to heat accumulation in high repetition rate femtosecond laser writing of buried optical waveguides,” Opt. Express 16, 9443–9458 (2008).
    [CrossRef] [PubMed]
  17. J. Morikawa and T. Hashimoto, “Thermal diffusivity of aromatic polyimide thin films by temperature wave analysis,” J. Appl. Phys. 105, 113506 (2009).
    [CrossRef]
  18. Y. Bellouard, M. Dugan, A. A. Said, and P. Bado, “Thermal conductivity contrast measurement of fused silica exposed to low-energy femtosecond laser pulses,” Appl. Phys. Lett. 89, 161911 (2006).
    [CrossRef]
  19. T. Hashimoto, S. Juodkazis, and H. Misawa, “Void recording in silica,” Appl. Phys. A 83, 337–340 (2006).
    [CrossRef]
  20. A. Marcinkevicius, V. Mizeikis, S. Juodkazis, S. Matsuo, and H. Misawa, “Effect of refractive index-mismatch on laser microfabrication in silica glass,” Appl. Phys. A. 76, 257–260 (2003).
    [CrossRef]
  21. E. E. Gamaly, S. Juodkazis, K. Nishimura, H. Misawa, B. Luther-Davies, L. Hallo, P. Nicolai, and V. Tikhonchuk, “Laser-matter interaction in a bulk of a transparent solid: confined micro-explosion and void formation,” Phys. Rev. B 73, 214101 (2006).
    [CrossRef]
  22. M. Shribak and R. Oldenbourg, “Techniques for fast and sensitive measurements of two-dimensional birefringence distributions,” Appl. Opt. 42, 3009–3017 (2003).
    [CrossRef] [PubMed]
  23. E. Vanagas, I. Kudryashov, D. Tuzhilin, S. Juodkazis, S. Matsuo, and H. Misawa, “Surface nanostructuring of borosilicate glass by femtosecond nJ energy pulses,” Appl. Phys. Lett. 82, 2901–2903 (2003).
    [CrossRef]
  24. S. Juodkazis, K. Yamasaki, V. Mizeikis, S. Matsuo, and H. Misawa, “Formation of embedded patterns in glasses using femtosecond irradiation,” Appl. Phys. A 79, 1549–1553 (2004).
    [CrossRef]
  25. S. Juodkazis, K. Nishimura, H. Misawa, T. Ebisui, R. Waki, S. Matsuo, and T. Okada, “Control over the state of crystallinity: Sapphire,” Adv. Mat. 18, 1361–1364 (2006).
    [CrossRef]
  26. S. Juodkazis, K. Nishimura, S. Tanaka, H. Misawa, E. E. Gamaly, B. Luther-Davies, L. Hallo, P. Nicolai, and V. Tikhonchuk, “Laser-induced microexplosion confined in the bulk of a sapphire crystal: Evidence of multimegabar pressures,” Phys. Rev. Lett. 96, 166101 (2006).
    [CrossRef] [PubMed]
  27. J. Morikawa, A. Orie, T. Hashimoto, and S. Juodkazis, “Thermal diffusivity in femtosecond-laser-structured micro-volumes of polymers,” Appl. Phys. A. 98, 551–556 (2010).
    [CrossRef]
  28. B. Rogers, S. Pennathur, and J. Adams, Nanotechnology: understanding small systems (CRC Press Taylor and Francis Group, Boca Raton, 2008).
  29. K. Ueno, S. Juodkazis, T. Shibuya, V. Mizeikis, Y. Yokota, and H. Misawa, “Nano-particle-enhanced photo-polymerization,” J. Phys. Chem. C 113, 11720–11724 (2009).
    [CrossRef]
  30. M. J. Assael, K. D. Antoniadis, and J. Wu, “New measurements of the thermal conductivity of PMMA, BK7, and Pyrex 7740 up to 450K,” Int. J. Thermophys. 292, 1257–1266 (2008).
    [CrossRef]
  31. Y. Bellouard, T. Colomb, C. Depeursinge, M. Dugan, A. A. Said, and P. Bado, “Nanoindentation and birefringence measurements on fused silica specimen exposed to low-energy femtosecond pulses,” Opt. Express 14, 8360–8366 (2006).
    [CrossRef] [PubMed]
  32. H. Aben, Photoelasticity of glass (Springer-Verlag Berlin, 1993).
  33. E. Brasselet, N. Murazawa, H. Misawa, and S. Juodkazis, “Optical vortices from liquid crystal droplets,” Phys. Rev. Lett. 103, 103903 (2009).
    [CrossRef] [PubMed]
  34. V. Mizeikis, S. Kimura, N. V. Surovtsev, V. Jarutis, A. Saito, H. Misawa, and S. Juodkazis, “Formation of amorphous sapphire by a femtosecond-pulse-induced micro-explosion,” Appl. Surf. Sci. 255, 9745–9749 (2009).
    [CrossRef]
  35. L. Allen, M. J. Padgett, and M. Babiker, “The orbital angular momentum of light,” Progress in Optics 39, 291–372 (1999).
    [CrossRef]
  36. M. Berry, “Making waves in physics,” Nature 403, 21 (2000).
    [CrossRef] [PubMed]
  37. K. T. Gahagan and G. A. Swartzlander, “Optical vortex trapping of particles,” Opt. Lett. 21, 827–829 (1996).
    [CrossRef] [PubMed]
  38. M. Harris, C. A. Hill, P. R. Tapster, and J. M. Vaughan, “Laser modes with helical wave fronts,” Phys. Rev. A 49, 3119–3122 (1994).
    [CrossRef] [PubMed]
  39. G. Foo, D. M. Palacios, and G. A. Swartzlander, “Optical vortex coronagraph,” Opt. Lett. 30, 3308–3310 (2005).
    [CrossRef]
  40. H. He, M. E. J. Friese, N. R. Heckenberg, and H. Rubinsztein-Dunlop, “Direct observation of transfer of angular-momentum to absorptive particles from a laser-beam with a phase singularity,” Phys. Rev. Lett. 75, 826–829 (1995).
    [CrossRef] [PubMed]
  41. P. G. Eliseev, S. Juodkazis, T. Sugahara, H.-B. Sun, S. Matsuo, S. Sakai, and H. Misawa, “GaN surface ablation by fs-pulses: atomic force microscopy studies, accumulation effects,” in Proceedings of High-Power Laser Ablation Conf. (SPIE Proc. 4065, 2000) pp.546–556.
  42. R. A. L. Jones, Soft Condensed Matter (Oxford University Press, 2002).
  43. A. K. Spilman and T. G. Brown, “Stress birefringent, space-variant wave plates for vortex illumination,” Appl. Optics 46, 61–66 (2007).
    [CrossRef]
  44. M. E. J. Friese, T. A. Nieminen, N. R. Heckenberg, and H. Rubinsztein-Dunlop, “Optical alignment and spinning of laser-trapped microscopic particles,” Nature 394, 348–350 (1998).
    [CrossRef]
  45. S. Juodkazis, M. Shikata, T. Takahashi, S. Matsuo, and H. Misawa, “Fast optical swithing by a laser manipulated microdroplet of liquid crystal,” Appl. Phys. Lett. 74, 3627–3629 (1999).
    [CrossRef]
  46. S. Juodkazis, S. Matsuo, N. Murazawa, I. Hasegawa, and H. Misawa, “High-efficiency optical transfer of torque to a nematic liquid crystal,” Appl. Phys. Lett. 82, 4657–4659 (2003).
    [CrossRef]
  47. E. Brasselet, Y. Izdebskaya, V. Shvedov, A. S. Desyatnikov, W. Krolikowski, and Y. S. Kivshar, “Dynamics of optical spin-orbit coupling in uniaxial crystals,” Opt. Lett. 34, 1021–1023 (2009).
    [CrossRef] [PubMed]
  48. A. Ciattoni, G. Cincotti, and C. Palma, “Angular momentum dynamics of a paraxial beam in a uniaxial crystal,” Phys. Rev. E 67, 036618 (2003).
    [CrossRef]
  49. L. Marrucci, C. Manzo, and D. Paparo, “Optical spin-to-orbital angular momentum conversion in inhomogeneous anisotropic media,” Phys. Rev. Lett. 96, 163905 (2006).
    [CrossRef] [PubMed]
  50. N. B. Simpson, K. Dholakia, L. Allen, and M. J. Padgett, “Mechanical equivalence of spin and orbital angular momentum of light: An optical spanner,” Opt. Lett. 22, 52–54 (1997).
    [CrossRef] [PubMed]
  51. H. Misawa and S. Juodkazis, “Photophysics and photochemistry of a laser manipulated microparticle,” Prog. Polym. Sci. 24, 665–697 (1999).
    [CrossRef]
  52. P. A. Williams, A. H. Rose, K. S. Lee, D. C. Conrad, G. W. Day, and P. D. Hale, “Optical, thermo-optic, electro-optic, and photoelastic properties of bismuth germanate ABi4Ge3O12B,” Appl. Opt. 35, 3562–3569 (1996).
    [CrossRef] [PubMed]
  53. “http://en.wikipedia.org/wiki/Hooke’s_law.”
  54. J. W. Kysar, “Path of light in near crack tip region in anisotropic medium and under mixed-mode loading,” Int. J. Sol. Struct. 38, 5963–5973 (2001).
    [CrossRef]
  55. J. Reintjes and M. B. Schulz, “Photoelastic constants of selected ultrasonic delay-line crystals,” J. Appl. Phys. 39, 5254–5258 (1968).
    [CrossRef]
  56. J. M. Winey, Y. M. Gupta, and D. E. Hare, “r-axis sound speed and elastic properties of sapphire single crystals,” J. Appl. Phys. 90, 3109–3111 (2001).
    [CrossRef]
  57. T. A. Davis and K. Vedam, “Photoelastic properties of sapphire (α - Al2O3),” J. Appl. Phys. 38, 4556–4557 (1967).
  58. M. Beresna, T. Gertus, R. Tomasiunas, H. Misawa, and S. Juodkazis, “Three-dimensional modeling of the heat-affected zone in laser machining applications,” Laser Chemistry 2008, 976205 (2008).
    [CrossRef]
  59. K. Syassen, “Ruby under pressure,” High Pressure Research 28, 75–126 (2008).
    [CrossRef]

2010 (2)

Y. Lan, A. J. Minnich, G. Chen, and Z. Ren, “Enhancement of thermoelectric figure-of-merit by a bulk nanostructuring approach,” Adv. Func. Mat.,  20, 357–376 (2010).
[CrossRef]

J. Morikawa, A. Orie, T. Hashimoto, and S. Juodkazis, “Thermal diffusivity in femtosecond-laser-structured micro-volumes of polymers,” Appl. Phys. A. 98, 551–556 (2010).
[CrossRef]

2009 (11)

K. Ueno, S. Juodkazis, T. Shibuya, V. Mizeikis, Y. Yokota, and H. Misawa, “Nano-particle-enhanced photo-polymerization,” J. Phys. Chem. C 113, 11720–11724 (2009).
[CrossRef]

E. Brasselet, N. Murazawa, H. Misawa, and S. Juodkazis, “Optical vortices from liquid crystal droplets,” Phys. Rev. Lett. 103, 103903 (2009).
[CrossRef] [PubMed]

V. Mizeikis, S. Kimura, N. V. Surovtsev, V. Jarutis, A. Saito, H. Misawa, and S. Juodkazis, “Formation of amorphous sapphire by a femtosecond-pulse-induced micro-explosion,” Appl. Surf. Sci. 255, 9745–9749 (2009).
[CrossRef]

S. Juodkazis, V. Mizeikis, and H. Misawa, “Three-dimensional microfabrication of materials by femtosecond lasers for photonics applications,” J. Appl. Phys. 106, 051101 (2009).
[CrossRef]

M. Ams, G. D. Marshall, P. Dekker, J. A. Piper, and M. J. Withford, “Ultrafast laser written active devices,” Laser Photon. Rev. 3, 535–544 (2009).
[CrossRef]

D. M. Krol, “Femtosecond laser modification of glass,” J. Non-Cryst. Sol. 354, 416–424 (2009).
[CrossRef]

J. Siebenmorgen, K. Petermann, G. Huber, K. Rademaker, and S. N. A. Tünnermann, “Femtosecond laser written stress-induced Nd:Y3Al5O12(Nd:YAG) channel waveguide laser,” Appl. Phys. B 97, 251–255 (2009).
[CrossRef]

J. Morikawa and T. Hashimoto, “Thermal diffusivity of aromatic polyimide thin films by temperature wave analysis,” J. Appl. Phys. 105, 113506 (2009).
[CrossRef]

E. Brasselet, Y. Izdebskaya, V. Shvedov, A. S. Desyatnikov, W. Krolikowski, and Y. S. Kivshar, “Dynamics of optical spin-orbit coupling in uniaxial crystals,” Opt. Lett. 34, 1021–1023 (2009).
[CrossRef] [PubMed]

G. Cheng, K. Mishchik, C. Mauclair, E. Audouard, and R. Stoian, “Ultrafast laser photoinscription of polarization sensitive devices in bulk silica glass,” Opt. Express 17, 9515–9525 (2009).
[CrossRef] [PubMed]

A. Benayas, D. Jaque, B. McMillen, and K. P. Chen, “High repetition rate UV ultrafast laser inscription of buried channel waveguides in sapphire: Fabrication and fluorescence imaging via ruby R lines,” Opt. Express 17, 10076–10081 (2009).
[CrossRef] [PubMed]

2008 (5)

S. M. Eaton, H. Zhang, M. L. Ng, J. Z. Li, W. J. Chen, S. Ho, and P. R. Herman, “Transition from thermal diffusion to heat accumulation in high repetition rate femtosecond laser writing of buried optical waveguides,” Opt. Express 16, 9443–9458 (2008).
[CrossRef] [PubMed]

M. Beresna, T. Gertus, R. Tomasiunas, H. Misawa, and S. Juodkazis, “Three-dimensional modeling of the heat-affected zone in laser machining applications,” Laser Chemistry 2008, 976205 (2008).
[CrossRef]

K. Syassen, “Ruby under pressure,” High Pressure Research 28, 75–126 (2008).
[CrossRef]

M. J. Assael, K. D. Antoniadis, and J. Wu, “New measurements of the thermal conductivity of PMMA, BK7, and Pyrex 7740 up to 450K,” Int. J. Thermophys. 292, 1257–1266 (2008).
[CrossRef]

J. Morikawa, C. Leong, T. Hashimoto, T. Ogawa, Y. Urata, S. Wada, M. Higuchi, and J.-I. Takahashi, “Thermal conductivity/diffusivity of Nd3+ doped GdVO4, YVO4, LuVO4,and Y3Al5O12 by temperature wave analysis,” J. Appl. Phys. 103, 063522 (2008).
[CrossRef]

2007 (1)

A. K. Spilman and T. G. Brown, “Stress birefringent, space-variant wave plates for vortex illumination,” Appl. Optics 46, 61–66 (2007).
[CrossRef]

2006 (8)

L. Marrucci, C. Manzo, and D. Paparo, “Optical spin-to-orbital angular momentum conversion in inhomogeneous anisotropic media,” Phys. Rev. Lett. 96, 163905 (2006).
[CrossRef] [PubMed]

E. E. Gamaly, S. Juodkazis, K. Nishimura, H. Misawa, B. Luther-Davies, L. Hallo, P. Nicolai, and V. Tikhonchuk, “Laser-matter interaction in a bulk of a transparent solid: confined micro-explosion and void formation,” Phys. Rev. B 73, 214101 (2006).
[CrossRef]

S. Juodkazis, K. Nishimura, H. Misawa, T. Ebisui, R. Waki, S. Matsuo, and T. Okada, “Control over the state of crystallinity: Sapphire,” Adv. Mat. 18, 1361–1364 (2006).
[CrossRef]

S. Juodkazis, K. Nishimura, S. Tanaka, H. Misawa, E. E. Gamaly, B. Luther-Davies, L. Hallo, P. Nicolai, and V. Tikhonchuk, “Laser-induced microexplosion confined in the bulk of a sapphire crystal: Evidence of multimegabar pressures,” Phys. Rev. Lett. 96, 166101 (2006).
[CrossRef] [PubMed]

Y. Bellouard, M. Dugan, A. A. Said, and P. Bado, “Thermal conductivity contrast measurement of fused silica exposed to low-energy femtosecond laser pulses,” Appl. Phys. Lett. 89, 161911 (2006).
[CrossRef]

T. Hashimoto, S. Juodkazis, and H. Misawa, “Void recording in silica,” Appl. Phys. A 83, 337–340 (2006).
[CrossRef]

S. Sowa, W. Watanabe, T. Tamaki, J. Nishii, and K. Itoh, “Symmetric waveguides in poly(methyl methacrylate) fabricated by femtosecond laser pulses,” Opt. Express 14, 291–297 (2006).
[CrossRef] [PubMed]

Y. Bellouard, T. Colomb, C. Depeursinge, M. Dugan, A. A. Said, and P. Bado, “Nanoindentation and birefringence measurements on fused silica specimen exposed to low-energy femtosecond pulses,” Opt. Express 14, 8360–8366 (2006).
[CrossRef] [PubMed]

2005 (2)

2004 (1)

S. Juodkazis, K. Yamasaki, V. Mizeikis, S. Matsuo, and H. Misawa, “Formation of embedded patterns in glasses using femtosecond irradiation,” Appl. Phys. A 79, 1549–1553 (2004).
[CrossRef]

2003 (7)

S. Juodkazis, S. Matsuo, N. Murazawa, I. Hasegawa, and H. Misawa, “High-efficiency optical transfer of torque to a nematic liquid crystal,” Appl. Phys. Lett. 82, 4657–4659 (2003).
[CrossRef]

A. Ciattoni, G. Cincotti, and C. Palma, “Angular momentum dynamics of a paraxial beam in a uniaxial crystal,” Phys. Rev. E 67, 036618 (2003).
[CrossRef]

A. Marcinkevicius, V. Mizeikis, S. Juodkazis, S. Matsuo, and H. Misawa, “Effect of refractive index-mismatch on laser microfabrication in silica glass,” Appl. Phys. A. 76, 257–260 (2003).
[CrossRef]

S. Nolte, M. Will, J. Burghoff, and A. Tünnermann, “Femtosecond waveguide writing: a new avenue to three-dimensional integrated optics,” Appl. Phys. A 77, 109–111 (2003).
[CrossRef]

E. Vanagas, I. Kudryashov, D. Tuzhilin, S. Juodkazis, S. Matsuo, and H. Misawa, “Surface nanostructuring of borosilicate glass by femtosecond nJ energy pulses,” Appl. Phys. Lett. 82, 2901–2903 (2003).
[CrossRef]

M. Shribak and R. Oldenbourg, “Techniques for fast and sensitive measurements of two-dimensional birefringence distributions,” Appl. Opt. 42, 3009–3017 (2003).
[CrossRef] [PubMed]

Z. Zhu and T. G. Brown, “Stress-induced birefringence in microstructured optical fibers,” Opt. Lett. 28, 2306–2308 (2003).
[CrossRef] [PubMed]

2002 (2)

2001 (2)

J. W. Kysar, “Path of light in near crack tip region in anisotropic medium and under mixed-mode loading,” Int. J. Sol. Struct. 38, 5963–5973 (2001).
[CrossRef]

J. M. Winey, Y. M. Gupta, and D. E. Hare, “r-axis sound speed and elastic properties of sapphire single crystals,” J. Appl. Phys. 90, 3109–3111 (2001).
[CrossRef]

2000 (1)

M. Berry, “Making waves in physics,” Nature 403, 21 (2000).
[CrossRef] [PubMed]

1999 (3)

S. Juodkazis, M. Shikata, T. Takahashi, S. Matsuo, and H. Misawa, “Fast optical swithing by a laser manipulated microdroplet of liquid crystal,” Appl. Phys. Lett. 74, 3627–3629 (1999).
[CrossRef]

H. Misawa and S. Juodkazis, “Photophysics and photochemistry of a laser manipulated microparticle,” Prog. Polym. Sci. 24, 665–697 (1999).
[CrossRef]

L. Allen, M. J. Padgett, and M. Babiker, “The orbital angular momentum of light,” Progress in Optics 39, 291–372 (1999).
[CrossRef]

1998 (1)

M. E. J. Friese, T. A. Nieminen, N. R. Heckenberg, and H. Rubinsztein-Dunlop, “Optical alignment and spinning of laser-trapped microscopic particles,” Nature 394, 348–350 (1998).
[CrossRef]

1997 (1)

1996 (2)

1995 (1)

H. He, M. E. J. Friese, N. R. Heckenberg, and H. Rubinsztein-Dunlop, “Direct observation of transfer of angular-momentum to absorptive particles from a laser-beam with a phase singularity,” Phys. Rev. Lett. 75, 826–829 (1995).
[CrossRef] [PubMed]

1994 (1)

M. Harris, C. A. Hill, P. R. Tapster, and J. M. Vaughan, “Laser modes with helical wave fronts,” Phys. Rev. A 49, 3119–3122 (1994).
[CrossRef] [PubMed]

1968 (1)

J. Reintjes and M. B. Schulz, “Photoelastic constants of selected ultrasonic delay-line crystals,” J. Appl. Phys. 39, 5254–5258 (1968).
[CrossRef]

1967 (1)

T. A. Davis and K. Vedam, “Photoelastic properties of sapphire (α - Al2O3),” J. Appl. Phys. 38, 4556–4557 (1967).

Aben, H.

H. Aben, Photoelasticity of glass (Springer-Verlag Berlin, 1993).

Adams, J.

B. Rogers, S. Pennathur, and J. Adams, Nanotechnology: understanding small systems (CRC Press Taylor and Francis Group, Boca Raton, 2008).

Allen, L.

Ams, M.

M. Ams, G. D. Marshall, P. Dekker, J. A. Piper, and M. J. Withford, “Ultrafast laser written active devices,” Laser Photon. Rev. 3, 535–544 (2009).
[CrossRef]

Antoniadis, K. D.

M. J. Assael, K. D. Antoniadis, and J. Wu, “New measurements of the thermal conductivity of PMMA, BK7, and Pyrex 7740 up to 450K,” Int. J. Thermophys. 292, 1257–1266 (2008).
[CrossRef]

Arai, A.

Assael, M. J.

M. J. Assael, K. D. Antoniadis, and J. Wu, “New measurements of the thermal conductivity of PMMA, BK7, and Pyrex 7740 up to 450K,” Int. J. Thermophys. 292, 1257–1266 (2008).
[CrossRef]

Audouard, E.

Babiker, M.

L. Allen, M. J. Padgett, and M. Babiker, “The orbital angular momentum of light,” Progress in Optics 39, 291–372 (1999).
[CrossRef]

Bado, P.

Y. Bellouard, M. Dugan, A. A. Said, and P. Bado, “Thermal conductivity contrast measurement of fused silica exposed to low-energy femtosecond laser pulses,” Appl. Phys. Lett. 89, 161911 (2006).
[CrossRef]

Y. Bellouard, T. Colomb, C. Depeursinge, M. Dugan, A. A. Said, and P. Bado, “Nanoindentation and birefringence measurements on fused silica specimen exposed to low-energy femtosecond pulses,” Opt. Express 14, 8360–8366 (2006).
[CrossRef] [PubMed]

Bellouard, Y.

Y. Bellouard, T. Colomb, C. Depeursinge, M. Dugan, A. A. Said, and P. Bado, “Nanoindentation and birefringence measurements on fused silica specimen exposed to low-energy femtosecond pulses,” Opt. Express 14, 8360–8366 (2006).
[CrossRef] [PubMed]

Y. Bellouard, M. Dugan, A. A. Said, and P. Bado, “Thermal conductivity contrast measurement of fused silica exposed to low-energy femtosecond laser pulses,” Appl. Phys. Lett. 89, 161911 (2006).
[CrossRef]

Benayas, A.

Beresna, M.

M. Beresna, T. Gertus, R. Tomasiunas, H. Misawa, and S. Juodkazis, “Three-dimensional modeling of the heat-affected zone in laser machining applications,” Laser Chemistry 2008, 976205 (2008).
[CrossRef]

Berry, M.

M. Berry, “Making waves in physics,” Nature 403, 21 (2000).
[CrossRef] [PubMed]

Brasselet, E.

Brown, T. G.

A. K. Spilman and T. G. Brown, “Stress birefringent, space-variant wave plates for vortex illumination,” Appl. Optics 46, 61–66 (2007).
[CrossRef]

Z. Zhu and T. G. Brown, “Stress-induced birefringence in microstructured optical fibers,” Opt. Lett. 28, 2306–2308 (2003).
[CrossRef] [PubMed]

Burghoff, J.

S. Nolte, M. Will, J. Burghoff, and A. Tünnermann, “Femtosecond waveguide writing: a new avenue to three-dimensional integrated optics,” Appl. Phys. A 77, 109–111 (2003).
[CrossRef]

Calmano, T.

J. Siebenmorgen, T. Calmano, O. Hellmig, K. Petermann, and G. Huber, “Efficient femtosecond laser written Nd:YAG channel waveguide laser with an output power of more than 1 W,”, Technical Digest, CLEO/Europe-EQEC Conference, 2009, paper CJ7.1.

Cerullo, G.

Chen, G.

Y. Lan, A. J. Minnich, G. Chen, and Z. Ren, “Enhancement of thermoelectric figure-of-merit by a bulk nanostructuring approach,” Adv. Func. Mat.,  20, 357–376 (2010).
[CrossRef]

Chen, K. P.

Chen, W. J.

Cheng, G.

Ciattoni, A.

A. Ciattoni, G. Cincotti, and C. Palma, “Angular momentum dynamics of a paraxial beam in a uniaxial crystal,” Phys. Rev. E 67, 036618 (2003).
[CrossRef]

Cincotti, G.

A. Ciattoni, G. Cincotti, and C. Palma, “Angular momentum dynamics of a paraxial beam in a uniaxial crystal,” Phys. Rev. E 67, 036618 (2003).
[CrossRef]

Colomb, T.

Conrad, D. C.

Davis, T. A.

T. A. Davis and K. Vedam, “Photoelastic properties of sapphire (α - Al2O3),” J. Appl. Phys. 38, 4556–4557 (1967).

Day, G. W.

Dekker, P.

M. Ams, G. D. Marshall, P. Dekker, J. A. Piper, and M. J. Withford, “Ultrafast laser written active devices,” Laser Photon. Rev. 3, 535–544 (2009).
[CrossRef]

Depeursinge, C.

Desyatnikov, A. S.

Dholakia, K.

Dugan, M.

Y. Bellouard, T. Colomb, C. Depeursinge, M. Dugan, A. A. Said, and P. Bado, “Nanoindentation and birefringence measurements on fused silica specimen exposed to low-energy femtosecond pulses,” Opt. Express 14, 8360–8366 (2006).
[CrossRef] [PubMed]

Y. Bellouard, M. Dugan, A. A. Said, and P. Bado, “Thermal conductivity contrast measurement of fused silica exposed to low-energy femtosecond laser pulses,” Appl. Phys. Lett. 89, 161911 (2006).
[CrossRef]

Eaton, S.

Eaton, S. M.

Ebisui, T.

S. Juodkazis, K. Nishimura, H. Misawa, T. Ebisui, R. Waki, S. Matsuo, and T. Okada, “Control over the state of crystallinity: Sapphire,” Adv. Mat. 18, 1361–1364 (2006).
[CrossRef]

Eliseev, P. G.

P. G. Eliseev, S. Juodkazis, T. Sugahara, H.-B. Sun, S. Matsuo, S. Sakai, and H. Misawa, “GaN surface ablation by fs-pulses: atomic force microscopy studies, accumulation effects,” in Proceedings of High-Power Laser Ablation Conf. (SPIE Proc. 4065, 2000) pp.546–556.

Foo, G.

Friese, M. E. J.

M. E. J. Friese, T. A. Nieminen, N. R. Heckenberg, and H. Rubinsztein-Dunlop, “Optical alignment and spinning of laser-trapped microscopic particles,” Nature 394, 348–350 (1998).
[CrossRef]

H. He, M. E. J. Friese, N. R. Heckenberg, and H. Rubinsztein-Dunlop, “Direct observation of transfer of angular-momentum to absorptive particles from a laser-beam with a phase singularity,” Phys. Rev. Lett. 75, 826–829 (1995).
[CrossRef] [PubMed]

Gahagan, K. T.

Gamaly, E. E.

S. Juodkazis, K. Nishimura, S. Tanaka, H. Misawa, E. E. Gamaly, B. Luther-Davies, L. Hallo, P. Nicolai, and V. Tikhonchuk, “Laser-induced microexplosion confined in the bulk of a sapphire crystal: Evidence of multimegabar pressures,” Phys. Rev. Lett. 96, 166101 (2006).
[CrossRef] [PubMed]

E. E. Gamaly, S. Juodkazis, K. Nishimura, H. Misawa, B. Luther-Davies, L. Hallo, P. Nicolai, and V. Tikhonchuk, “Laser-matter interaction in a bulk of a transparent solid: confined micro-explosion and void formation,” Phys. Rev. B 73, 214101 (2006).
[CrossRef]

Gertus, T.

M. Beresna, T. Gertus, R. Tomasiunas, H. Misawa, and S. Juodkazis, “Three-dimensional modeling of the heat-affected zone in laser machining applications,” Laser Chemistry 2008, 976205 (2008).
[CrossRef]

Gupta, Y. M.

J. M. Winey, Y. M. Gupta, and D. E. Hare, “r-axis sound speed and elastic properties of sapphire single crystals,” J. Appl. Phys. 90, 3109–3111 (2001).
[CrossRef]

Hale, P. D.

Hallo, L.

E. E. Gamaly, S. Juodkazis, K. Nishimura, H. Misawa, B. Luther-Davies, L. Hallo, P. Nicolai, and V. Tikhonchuk, “Laser-matter interaction in a bulk of a transparent solid: confined micro-explosion and void formation,” Phys. Rev. B 73, 214101 (2006).
[CrossRef]

S. Juodkazis, K. Nishimura, S. Tanaka, H. Misawa, E. E. Gamaly, B. Luther-Davies, L. Hallo, P. Nicolai, and V. Tikhonchuk, “Laser-induced microexplosion confined in the bulk of a sapphire crystal: Evidence of multimegabar pressures,” Phys. Rev. Lett. 96, 166101 (2006).
[CrossRef] [PubMed]

Hare, D. E.

J. M. Winey, Y. M. Gupta, and D. E. Hare, “r-axis sound speed and elastic properties of sapphire single crystals,” J. Appl. Phys. 90, 3109–3111 (2001).
[CrossRef]

Harris, M.

M. Harris, C. A. Hill, P. R. Tapster, and J. M. Vaughan, “Laser modes with helical wave fronts,” Phys. Rev. A 49, 3119–3122 (1994).
[CrossRef] [PubMed]

Hasegawa, I.

S. Juodkazis, S. Matsuo, N. Murazawa, I. Hasegawa, and H. Misawa, “High-efficiency optical transfer of torque to a nematic liquid crystal,” Appl. Phys. Lett. 82, 4657–4659 (2003).
[CrossRef]

Hashimoto, T.

J. Morikawa, A. Orie, T. Hashimoto, and S. Juodkazis, “Thermal diffusivity in femtosecond-laser-structured micro-volumes of polymers,” Appl. Phys. A. 98, 551–556 (2010).
[CrossRef]

J. Morikawa and T. Hashimoto, “Thermal diffusivity of aromatic polyimide thin films by temperature wave analysis,” J. Appl. Phys. 105, 113506 (2009).
[CrossRef]

J. Morikawa, C. Leong, T. Hashimoto, T. Ogawa, Y. Urata, S. Wada, M. Higuchi, and J.-I. Takahashi, “Thermal conductivity/diffusivity of Nd3+ doped GdVO4, YVO4, LuVO4,and Y3Al5O12 by temperature wave analysis,” J. Appl. Phys. 103, 063522 (2008).
[CrossRef]

T. Hashimoto, S. Juodkazis, and H. Misawa, “Void recording in silica,” Appl. Phys. A 83, 337–340 (2006).
[CrossRef]

He, H.

H. He, M. E. J. Friese, N. R. Heckenberg, and H. Rubinsztein-Dunlop, “Direct observation of transfer of angular-momentum to absorptive particles from a laser-beam with a phase singularity,” Phys. Rev. Lett. 75, 826–829 (1995).
[CrossRef] [PubMed]

Heckenberg, N. R.

M. E. J. Friese, T. A. Nieminen, N. R. Heckenberg, and H. Rubinsztein-Dunlop, “Optical alignment and spinning of laser-trapped microscopic particles,” Nature 394, 348–350 (1998).
[CrossRef]

H. He, M. E. J. Friese, N. R. Heckenberg, and H. Rubinsztein-Dunlop, “Direct observation of transfer of angular-momentum to absorptive particles from a laser-beam with a phase singularity,” Phys. Rev. Lett. 75, 826–829 (1995).
[CrossRef] [PubMed]

Hellmig, O.

J. Siebenmorgen, T. Calmano, O. Hellmig, K. Petermann, and G. Huber, “Efficient femtosecond laser written Nd:YAG channel waveguide laser with an output power of more than 1 W,”, Technical Digest, CLEO/Europe-EQEC Conference, 2009, paper CJ7.1.

Herman, P

Herman, P. R.

Higuchi, M.

J. Morikawa, C. Leong, T. Hashimoto, T. Ogawa, Y. Urata, S. Wada, M. Higuchi, and J.-I. Takahashi, “Thermal conductivity/diffusivity of Nd3+ doped GdVO4, YVO4, LuVO4,and Y3Al5O12 by temperature wave analysis,” J. Appl. Phys. 103, 063522 (2008).
[CrossRef]

Hill, C. A.

M. Harris, C. A. Hill, P. R. Tapster, and J. M. Vaughan, “Laser modes with helical wave fronts,” Phys. Rev. A 49, 3119–3122 (1994).
[CrossRef] [PubMed]

Ho, S.

Huber, G.

J. Siebenmorgen, K. Petermann, G. Huber, K. Rademaker, and S. N. A. Tünnermann, “Femtosecond laser written stress-induced Nd:Y3Al5O12(Nd:YAG) channel waveguide laser,” Appl. Phys. B 97, 251–255 (2009).
[CrossRef]

J. Siebenmorgen, T. Calmano, O. Hellmig, K. Petermann, and G. Huber, “Efficient femtosecond laser written Nd:YAG channel waveguide laser with an output power of more than 1 W,”, Technical Digest, CLEO/Europe-EQEC Conference, 2009, paper CJ7.1.

Itoh, K.

Izdebskaya, Y.

Jaque, D.

Jarutis, V.

V. Mizeikis, S. Kimura, N. V. Surovtsev, V. Jarutis, A. Saito, H. Misawa, and S. Juodkazis, “Formation of amorphous sapphire by a femtosecond-pulse-induced micro-explosion,” Appl. Surf. Sci. 255, 9745–9749 (2009).
[CrossRef]

Jones, R. A. L.

R. A. L. Jones, Soft Condensed Matter (Oxford University Press, 2002).

Juodkazis, S.

J. Morikawa, A. Orie, T. Hashimoto, and S. Juodkazis, “Thermal diffusivity in femtosecond-laser-structured micro-volumes of polymers,” Appl. Phys. A. 98, 551–556 (2010).
[CrossRef]

K. Ueno, S. Juodkazis, T. Shibuya, V. Mizeikis, Y. Yokota, and H. Misawa, “Nano-particle-enhanced photo-polymerization,” J. Phys. Chem. C 113, 11720–11724 (2009).
[CrossRef]

E. Brasselet, N. Murazawa, H. Misawa, and S. Juodkazis, “Optical vortices from liquid crystal droplets,” Phys. Rev. Lett. 103, 103903 (2009).
[CrossRef] [PubMed]

V. Mizeikis, S. Kimura, N. V. Surovtsev, V. Jarutis, A. Saito, H. Misawa, and S. Juodkazis, “Formation of amorphous sapphire by a femtosecond-pulse-induced micro-explosion,” Appl. Surf. Sci. 255, 9745–9749 (2009).
[CrossRef]

S. Juodkazis, V. Mizeikis, and H. Misawa, “Three-dimensional microfabrication of materials by femtosecond lasers for photonics applications,” J. Appl. Phys. 106, 051101 (2009).
[CrossRef]

M. Beresna, T. Gertus, R. Tomasiunas, H. Misawa, and S. Juodkazis, “Three-dimensional modeling of the heat-affected zone in laser machining applications,” Laser Chemistry 2008, 976205 (2008).
[CrossRef]

T. Hashimoto, S. Juodkazis, and H. Misawa, “Void recording in silica,” Appl. Phys. A 83, 337–340 (2006).
[CrossRef]

E. E. Gamaly, S. Juodkazis, K. Nishimura, H. Misawa, B. Luther-Davies, L. Hallo, P. Nicolai, and V. Tikhonchuk, “Laser-matter interaction in a bulk of a transparent solid: confined micro-explosion and void formation,” Phys. Rev. B 73, 214101 (2006).
[CrossRef]

S. Juodkazis, K. Nishimura, H. Misawa, T. Ebisui, R. Waki, S. Matsuo, and T. Okada, “Control over the state of crystallinity: Sapphire,” Adv. Mat. 18, 1361–1364 (2006).
[CrossRef]

S. Juodkazis, K. Nishimura, S. Tanaka, H. Misawa, E. E. Gamaly, B. Luther-Davies, L. Hallo, P. Nicolai, and V. Tikhonchuk, “Laser-induced microexplosion confined in the bulk of a sapphire crystal: Evidence of multimegabar pressures,” Phys. Rev. Lett. 96, 166101 (2006).
[CrossRef] [PubMed]

S. Juodkazis, K. Yamasaki, V. Mizeikis, S. Matsuo, and H. Misawa, “Formation of embedded patterns in glasses using femtosecond irradiation,” Appl. Phys. A 79, 1549–1553 (2004).
[CrossRef]

E. Vanagas, I. Kudryashov, D. Tuzhilin, S. Juodkazis, S. Matsuo, and H. Misawa, “Surface nanostructuring of borosilicate glass by femtosecond nJ energy pulses,” Appl. Phys. Lett. 82, 2901–2903 (2003).
[CrossRef]

A. Marcinkevicius, V. Mizeikis, S. Juodkazis, S. Matsuo, and H. Misawa, “Effect of refractive index-mismatch on laser microfabrication in silica glass,” Appl. Phys. A. 76, 257–260 (2003).
[CrossRef]

S. Juodkazis, S. Matsuo, N. Murazawa, I. Hasegawa, and H. Misawa, “High-efficiency optical transfer of torque to a nematic liquid crystal,” Appl. Phys. Lett. 82, 4657–4659 (2003).
[CrossRef]

H. Misawa and S. Juodkazis, “Photophysics and photochemistry of a laser manipulated microparticle,” Prog. Polym. Sci. 24, 665–697 (1999).
[CrossRef]

S. Juodkazis, M. Shikata, T. Takahashi, S. Matsuo, and H. Misawa, “Fast optical swithing by a laser manipulated microdroplet of liquid crystal,” Appl. Phys. Lett. 74, 3627–3629 (1999).
[CrossRef]

P. G. Eliseev, S. Juodkazis, T. Sugahara, H.-B. Sun, S. Matsuo, S. Sakai, and H. Misawa, “GaN surface ablation by fs-pulses: atomic force microscopy studies, accumulation effects,” in Proceedings of High-Power Laser Ablation Conf. (SPIE Proc. 4065, 2000) pp.546–556.

Kimura, S.

V. Mizeikis, S. Kimura, N. V. Surovtsev, V. Jarutis, A. Saito, H. Misawa, and S. Juodkazis, “Formation of amorphous sapphire by a femtosecond-pulse-induced micro-explosion,” Appl. Surf. Sci. 255, 9745–9749 (2009).
[CrossRef]

Kivshar, Y. S.

Krol, D. M.

D. M. Krol, “Femtosecond laser modification of glass,” J. Non-Cryst. Sol. 354, 416–424 (2009).
[CrossRef]

Krolikowski, W.

Kudryashov, I.

E. Vanagas, I. Kudryashov, D. Tuzhilin, S. Juodkazis, S. Matsuo, and H. Misawa, “Surface nanostructuring of borosilicate glass by femtosecond nJ energy pulses,” Appl. Phys. Lett. 82, 2901–2903 (2003).
[CrossRef]

Kysar, J. W.

J. W. Kysar, “Path of light in near crack tip region in anisotropic medium and under mixed-mode loading,” Int. J. Sol. Struct. 38, 5963–5973 (2001).
[CrossRef]

Lan, Y.

Y. Lan, A. J. Minnich, G. Chen, and Z. Ren, “Enhancement of thermoelectric figure-of-merit by a bulk nanostructuring approach,” Adv. Func. Mat.,  20, 357–376 (2010).
[CrossRef]

Laporta, P.

Lee, K. S.

Leong, C.

J. Morikawa, C. Leong, T. Hashimoto, T. Ogawa, Y. Urata, S. Wada, M. Higuchi, and J.-I. Takahashi, “Thermal conductivity/diffusivity of Nd3+ doped GdVO4, YVO4, LuVO4,and Y3Al5O12 by temperature wave analysis,” J. Appl. Phys. 103, 063522 (2008).
[CrossRef]

Li, J. Z.

Luther-Davies, B.

E. E. Gamaly, S. Juodkazis, K. Nishimura, H. Misawa, B. Luther-Davies, L. Hallo, P. Nicolai, and V. Tikhonchuk, “Laser-matter interaction in a bulk of a transparent solid: confined micro-explosion and void formation,” Phys. Rev. B 73, 214101 (2006).
[CrossRef]

S. Juodkazis, K. Nishimura, S. Tanaka, H. Misawa, E. E. Gamaly, B. Luther-Davies, L. Hallo, P. Nicolai, and V. Tikhonchuk, “Laser-induced microexplosion confined in the bulk of a sapphire crystal: Evidence of multimegabar pressures,” Phys. Rev. Lett. 96, 166101 (2006).
[CrossRef] [PubMed]

Manzo, C.

L. Marrucci, C. Manzo, and D. Paparo, “Optical spin-to-orbital angular momentum conversion in inhomogeneous anisotropic media,” Phys. Rev. Lett. 96, 163905 (2006).
[CrossRef] [PubMed]

Marangoni, M.

Marcinkevicius, A.

A. Marcinkevicius, V. Mizeikis, S. Juodkazis, S. Matsuo, and H. Misawa, “Effect of refractive index-mismatch on laser microfabrication in silica glass,” Appl. Phys. A. 76, 257–260 (2003).
[CrossRef]

Marrucci, L.

L. Marrucci, C. Manzo, and D. Paparo, “Optical spin-to-orbital angular momentum conversion in inhomogeneous anisotropic media,” Phys. Rev. Lett. 96, 163905 (2006).
[CrossRef] [PubMed]

Marshall, G. D.

M. Ams, G. D. Marshall, P. Dekker, J. A. Piper, and M. J. Withford, “Ultrafast laser written active devices,” Laser Photon. Rev. 3, 535–544 (2009).
[CrossRef]

Matsuo, S.

S. Juodkazis, K. Nishimura, H. Misawa, T. Ebisui, R. Waki, S. Matsuo, and T. Okada, “Control over the state of crystallinity: Sapphire,” Adv. Mat. 18, 1361–1364 (2006).
[CrossRef]

S. Juodkazis, K. Yamasaki, V. Mizeikis, S. Matsuo, and H. Misawa, “Formation of embedded patterns in glasses using femtosecond irradiation,” Appl. Phys. A 79, 1549–1553 (2004).
[CrossRef]

E. Vanagas, I. Kudryashov, D. Tuzhilin, S. Juodkazis, S. Matsuo, and H. Misawa, “Surface nanostructuring of borosilicate glass by femtosecond nJ energy pulses,” Appl. Phys. Lett. 82, 2901–2903 (2003).
[CrossRef]

A. Marcinkevicius, V. Mizeikis, S. Juodkazis, S. Matsuo, and H. Misawa, “Effect of refractive index-mismatch on laser microfabrication in silica glass,” Appl. Phys. A. 76, 257–260 (2003).
[CrossRef]

S. Juodkazis, S. Matsuo, N. Murazawa, I. Hasegawa, and H. Misawa, “High-efficiency optical transfer of torque to a nematic liquid crystal,” Appl. Phys. Lett. 82, 4657–4659 (2003).
[CrossRef]

S. Juodkazis, M. Shikata, T. Takahashi, S. Matsuo, and H. Misawa, “Fast optical swithing by a laser manipulated microdroplet of liquid crystal,” Appl. Phys. Lett. 74, 3627–3629 (1999).
[CrossRef]

P. G. Eliseev, S. Juodkazis, T. Sugahara, H.-B. Sun, S. Matsuo, S. Sakai, and H. Misawa, “GaN surface ablation by fs-pulses: atomic force microscopy studies, accumulation effects,” in Proceedings of High-Power Laser Ablation Conf. (SPIE Proc. 4065, 2000) pp.546–556.

Mauclair, C.

Mazur, E.

S. K. Sundaram and E. Mazur, “Inducing and probing non-thermal transitions in semiconductors using femtosecond laser pulses,” Nature Mat. 1, 217–224 (2002).
[CrossRef]

McMillen, B.

Minnich, A. J.

Y. Lan, A. J. Minnich, G. Chen, and Z. Ren, “Enhancement of thermoelectric figure-of-merit by a bulk nanostructuring approach,” Adv. Func. Mat.,  20, 357–376 (2010).
[CrossRef]

Misawa, H.

S. Juodkazis, V. Mizeikis, and H. Misawa, “Three-dimensional microfabrication of materials by femtosecond lasers for photonics applications,” J. Appl. Phys. 106, 051101 (2009).
[CrossRef]

V. Mizeikis, S. Kimura, N. V. Surovtsev, V. Jarutis, A. Saito, H. Misawa, and S. Juodkazis, “Formation of amorphous sapphire by a femtosecond-pulse-induced micro-explosion,” Appl. Surf. Sci. 255, 9745–9749 (2009).
[CrossRef]

E. Brasselet, N. Murazawa, H. Misawa, and S. Juodkazis, “Optical vortices from liquid crystal droplets,” Phys. Rev. Lett. 103, 103903 (2009).
[CrossRef] [PubMed]

K. Ueno, S. Juodkazis, T. Shibuya, V. Mizeikis, Y. Yokota, and H. Misawa, “Nano-particle-enhanced photo-polymerization,” J. Phys. Chem. C 113, 11720–11724 (2009).
[CrossRef]

M. Beresna, T. Gertus, R. Tomasiunas, H. Misawa, and S. Juodkazis, “Three-dimensional modeling of the heat-affected zone in laser machining applications,” Laser Chemistry 2008, 976205 (2008).
[CrossRef]

S. Juodkazis, K. Nishimura, H. Misawa, T. Ebisui, R. Waki, S. Matsuo, and T. Okada, “Control over the state of crystallinity: Sapphire,” Adv. Mat. 18, 1361–1364 (2006).
[CrossRef]

S. Juodkazis, K. Nishimura, S. Tanaka, H. Misawa, E. E. Gamaly, B. Luther-Davies, L. Hallo, P. Nicolai, and V. Tikhonchuk, “Laser-induced microexplosion confined in the bulk of a sapphire crystal: Evidence of multimegabar pressures,” Phys. Rev. Lett. 96, 166101 (2006).
[CrossRef] [PubMed]

T. Hashimoto, S. Juodkazis, and H. Misawa, “Void recording in silica,” Appl. Phys. A 83, 337–340 (2006).
[CrossRef]

E. E. Gamaly, S. Juodkazis, K. Nishimura, H. Misawa, B. Luther-Davies, L. Hallo, P. Nicolai, and V. Tikhonchuk, “Laser-matter interaction in a bulk of a transparent solid: confined micro-explosion and void formation,” Phys. Rev. B 73, 214101 (2006).
[CrossRef]

S. Juodkazis, K. Yamasaki, V. Mizeikis, S. Matsuo, and H. Misawa, “Formation of embedded patterns in glasses using femtosecond irradiation,” Appl. Phys. A 79, 1549–1553 (2004).
[CrossRef]

E. Vanagas, I. Kudryashov, D. Tuzhilin, S. Juodkazis, S. Matsuo, and H. Misawa, “Surface nanostructuring of borosilicate glass by femtosecond nJ energy pulses,” Appl. Phys. Lett. 82, 2901–2903 (2003).
[CrossRef]

A. Marcinkevicius, V. Mizeikis, S. Juodkazis, S. Matsuo, and H. Misawa, “Effect of refractive index-mismatch on laser microfabrication in silica glass,” Appl. Phys. A. 76, 257–260 (2003).
[CrossRef]

S. Juodkazis, S. Matsuo, N. Murazawa, I. Hasegawa, and H. Misawa, “High-efficiency optical transfer of torque to a nematic liquid crystal,” Appl. Phys. Lett. 82, 4657–4659 (2003).
[CrossRef]

H. Misawa and S. Juodkazis, “Photophysics and photochemistry of a laser manipulated microparticle,” Prog. Polym. Sci. 24, 665–697 (1999).
[CrossRef]

S. Juodkazis, M. Shikata, T. Takahashi, S. Matsuo, and H. Misawa, “Fast optical swithing by a laser manipulated microdroplet of liquid crystal,” Appl. Phys. Lett. 74, 3627–3629 (1999).
[CrossRef]

P. G. Eliseev, S. Juodkazis, T. Sugahara, H.-B. Sun, S. Matsuo, S. Sakai, and H. Misawa, “GaN surface ablation by fs-pulses: atomic force microscopy studies, accumulation effects,” in Proceedings of High-Power Laser Ablation Conf. (SPIE Proc. 4065, 2000) pp.546–556.

Mishchik, K.

Mizeikis, V.

K. Ueno, S. Juodkazis, T. Shibuya, V. Mizeikis, Y. Yokota, and H. Misawa, “Nano-particle-enhanced photo-polymerization,” J. Phys. Chem. C 113, 11720–11724 (2009).
[CrossRef]

V. Mizeikis, S. Kimura, N. V. Surovtsev, V. Jarutis, A. Saito, H. Misawa, and S. Juodkazis, “Formation of amorphous sapphire by a femtosecond-pulse-induced micro-explosion,” Appl. Surf. Sci. 255, 9745–9749 (2009).
[CrossRef]

S. Juodkazis, V. Mizeikis, and H. Misawa, “Three-dimensional microfabrication of materials by femtosecond lasers for photonics applications,” J. Appl. Phys. 106, 051101 (2009).
[CrossRef]

S. Juodkazis, K. Yamasaki, V. Mizeikis, S. Matsuo, and H. Misawa, “Formation of embedded patterns in glasses using femtosecond irradiation,” Appl. Phys. A 79, 1549–1553 (2004).
[CrossRef]

A. Marcinkevicius, V. Mizeikis, S. Juodkazis, S. Matsuo, and H. Misawa, “Effect of refractive index-mismatch on laser microfabrication in silica glass,” Appl. Phys. A. 76, 257–260 (2003).
[CrossRef]

Morikawa, J.

J. Morikawa, A. Orie, T. Hashimoto, and S. Juodkazis, “Thermal diffusivity in femtosecond-laser-structured micro-volumes of polymers,” Appl. Phys. A. 98, 551–556 (2010).
[CrossRef]

J. Morikawa and T. Hashimoto, “Thermal diffusivity of aromatic polyimide thin films by temperature wave analysis,” J. Appl. Phys. 105, 113506 (2009).
[CrossRef]

J. Morikawa, C. Leong, T. Hashimoto, T. Ogawa, Y. Urata, S. Wada, M. Higuchi, and J.-I. Takahashi, “Thermal conductivity/diffusivity of Nd3+ doped GdVO4, YVO4, LuVO4,and Y3Al5O12 by temperature wave analysis,” J. Appl. Phys. 103, 063522 (2008).
[CrossRef]

Murazawa, N.

E. Brasselet, N. Murazawa, H. Misawa, and S. Juodkazis, “Optical vortices from liquid crystal droplets,” Phys. Rev. Lett. 103, 103903 (2009).
[CrossRef] [PubMed]

S. Juodkazis, S. Matsuo, N. Murazawa, I. Hasegawa, and H. Misawa, “High-efficiency optical transfer of torque to a nematic liquid crystal,” Appl. Phys. Lett. 82, 4657–4659 (2003).
[CrossRef]

Ng, M. L.

Nicolai, P.

S. Juodkazis, K. Nishimura, S. Tanaka, H. Misawa, E. E. Gamaly, B. Luther-Davies, L. Hallo, P. Nicolai, and V. Tikhonchuk, “Laser-induced microexplosion confined in the bulk of a sapphire crystal: Evidence of multimegabar pressures,” Phys. Rev. Lett. 96, 166101 (2006).
[CrossRef] [PubMed]

E. E. Gamaly, S. Juodkazis, K. Nishimura, H. Misawa, B. Luther-Davies, L. Hallo, P. Nicolai, and V. Tikhonchuk, “Laser-matter interaction in a bulk of a transparent solid: confined micro-explosion and void formation,” Phys. Rev. B 73, 214101 (2006).
[CrossRef]

Nieminen, T. A.

M. E. J. Friese, T. A. Nieminen, N. R. Heckenberg, and H. Rubinsztein-Dunlop, “Optical alignment and spinning of laser-trapped microscopic particles,” Nature 394, 348–350 (1998).
[CrossRef]

Nishii, J.

Nishimura, K.

S. Juodkazis, K. Nishimura, S. Tanaka, H. Misawa, E. E. Gamaly, B. Luther-Davies, L. Hallo, P. Nicolai, and V. Tikhonchuk, “Laser-induced microexplosion confined in the bulk of a sapphire crystal: Evidence of multimegabar pressures,” Phys. Rev. Lett. 96, 166101 (2006).
[CrossRef] [PubMed]

E. E. Gamaly, S. Juodkazis, K. Nishimura, H. Misawa, B. Luther-Davies, L. Hallo, P. Nicolai, and V. Tikhonchuk, “Laser-matter interaction in a bulk of a transparent solid: confined micro-explosion and void formation,” Phys. Rev. B 73, 214101 (2006).
[CrossRef]

S. Juodkazis, K. Nishimura, H. Misawa, T. Ebisui, R. Waki, S. Matsuo, and T. Okada, “Control over the state of crystallinity: Sapphire,” Adv. Mat. 18, 1361–1364 (2006).
[CrossRef]

Nolte, S.

S. Nolte, M. Will, J. Burghoff, and A. Tünnermann, “Femtosecond waveguide writing: a new avenue to three-dimensional integrated optics,” Appl. Phys. A 77, 109–111 (2003).
[CrossRef]

Ogawa, T.

J. Morikawa, C. Leong, T. Hashimoto, T. Ogawa, Y. Urata, S. Wada, M. Higuchi, and J.-I. Takahashi, “Thermal conductivity/diffusivity of Nd3+ doped GdVO4, YVO4, LuVO4,and Y3Al5O12 by temperature wave analysis,” J. Appl. Phys. 103, 063522 (2008).
[CrossRef]

Okada, T.

S. Juodkazis, K. Nishimura, H. Misawa, T. Ebisui, R. Waki, S. Matsuo, and T. Okada, “Control over the state of crystallinity: Sapphire,” Adv. Mat. 18, 1361–1364 (2006).
[CrossRef]

Oldenbourg, R.

Orie, A.

J. Morikawa, A. Orie, T. Hashimoto, and S. Juodkazis, “Thermal diffusivity in femtosecond-laser-structured micro-volumes of polymers,” Appl. Phys. A. 98, 551–556 (2010).
[CrossRef]

Osellame, R.

Padgett, M. J.

Palacios, D. M.

Palma, C.

A. Ciattoni, G. Cincotti, and C. Palma, “Angular momentum dynamics of a paraxial beam in a uniaxial crystal,” Phys. Rev. E 67, 036618 (2003).
[CrossRef]

Paparo, D.

L. Marrucci, C. Manzo, and D. Paparo, “Optical spin-to-orbital angular momentum conversion in inhomogeneous anisotropic media,” Phys. Rev. Lett. 96, 163905 (2006).
[CrossRef] [PubMed]

Pennathur, S.

B. Rogers, S. Pennathur, and J. Adams, Nanotechnology: understanding small systems (CRC Press Taylor and Francis Group, Boca Raton, 2008).

Petermann, K.

J. Siebenmorgen, K. Petermann, G. Huber, K. Rademaker, and S. N. A. Tünnermann, “Femtosecond laser written stress-induced Nd:Y3Al5O12(Nd:YAG) channel waveguide laser,” Appl. Phys. B 97, 251–255 (2009).
[CrossRef]

J. Siebenmorgen, T. Calmano, O. Hellmig, K. Petermann, and G. Huber, “Efficient femtosecond laser written Nd:YAG channel waveguide laser with an output power of more than 1 W,”, Technical Digest, CLEO/Europe-EQEC Conference, 2009, paper CJ7.1.

Piper, J. A.

M. Ams, G. D. Marshall, P. Dekker, J. A. Piper, and M. J. Withford, “Ultrafast laser written active devices,” Laser Photon. Rev. 3, 535–544 (2009).
[CrossRef]

Polli, D.

Rademaker, K.

J. Siebenmorgen, K. Petermann, G. Huber, K. Rademaker, and S. N. A. Tünnermann, “Femtosecond laser written stress-induced Nd:Y3Al5O12(Nd:YAG) channel waveguide laser,” Appl. Phys. B 97, 251–255 (2009).
[CrossRef]

Ramponi, R.

Reintjes, J.

J. Reintjes and M. B. Schulz, “Photoelastic constants of selected ultrasonic delay-line crystals,” J. Appl. Phys. 39, 5254–5258 (1968).
[CrossRef]

Ren, Z.

Y. Lan, A. J. Minnich, G. Chen, and Z. Ren, “Enhancement of thermoelectric figure-of-merit by a bulk nanostructuring approach,” Adv. Func. Mat.,  20, 357–376 (2010).
[CrossRef]

Rogers, B.

B. Rogers, S. Pennathur, and J. Adams, Nanotechnology: understanding small systems (CRC Press Taylor and Francis Group, Boca Raton, 2008).

Rose, A. H.

Rubinsztein-Dunlop, H.

M. E. J. Friese, T. A. Nieminen, N. R. Heckenberg, and H. Rubinsztein-Dunlop, “Optical alignment and spinning of laser-trapped microscopic particles,” Nature 394, 348–350 (1998).
[CrossRef]

H. He, M. E. J. Friese, N. R. Heckenberg, and H. Rubinsztein-Dunlop, “Direct observation of transfer of angular-momentum to absorptive particles from a laser-beam with a phase singularity,” Phys. Rev. Lett. 75, 826–829 (1995).
[CrossRef] [PubMed]

Said, A. A.

Y. Bellouard, M. Dugan, A. A. Said, and P. Bado, “Thermal conductivity contrast measurement of fused silica exposed to low-energy femtosecond laser pulses,” Appl. Phys. Lett. 89, 161911 (2006).
[CrossRef]

Y. Bellouard, T. Colomb, C. Depeursinge, M. Dugan, A. A. Said, and P. Bado, “Nanoindentation and birefringence measurements on fused silica specimen exposed to low-energy femtosecond pulses,” Opt. Express 14, 8360–8366 (2006).
[CrossRef] [PubMed]

Saito, A.

V. Mizeikis, S. Kimura, N. V. Surovtsev, V. Jarutis, A. Saito, H. Misawa, and S. Juodkazis, “Formation of amorphous sapphire by a femtosecond-pulse-induced micro-explosion,” Appl. Surf. Sci. 255, 9745–9749 (2009).
[CrossRef]

Sakai, S.

P. G. Eliseev, S. Juodkazis, T. Sugahara, H.-B. Sun, S. Matsuo, S. Sakai, and H. Misawa, “GaN surface ablation by fs-pulses: atomic force microscopy studies, accumulation effects,” in Proceedings of High-Power Laser Ablation Conf. (SPIE Proc. 4065, 2000) pp.546–556.

Schulz, M. B.

J. Reintjes and M. B. Schulz, “Photoelastic constants of selected ultrasonic delay-line crystals,” J. Appl. Phys. 39, 5254–5258 (1968).
[CrossRef]

Shah, L.

Shibuya, T.

K. Ueno, S. Juodkazis, T. Shibuya, V. Mizeikis, Y. Yokota, and H. Misawa, “Nano-particle-enhanced photo-polymerization,” J. Phys. Chem. C 113, 11720–11724 (2009).
[CrossRef]

Shikata, M.

S. Juodkazis, M. Shikata, T. Takahashi, S. Matsuo, and H. Misawa, “Fast optical swithing by a laser manipulated microdroplet of liquid crystal,” Appl. Phys. Lett. 74, 3627–3629 (1999).
[CrossRef]

Shribak, M.

Shvedov, V.

Siebenmorgen, J.

J. Siebenmorgen, K. Petermann, G. Huber, K. Rademaker, and S. N. A. Tünnermann, “Femtosecond laser written stress-induced Nd:Y3Al5O12(Nd:YAG) channel waveguide laser,” Appl. Phys. B 97, 251–255 (2009).
[CrossRef]

J. Siebenmorgen, T. Calmano, O. Hellmig, K. Petermann, and G. Huber, “Efficient femtosecond laser written Nd:YAG channel waveguide laser with an output power of more than 1 W,”, Technical Digest, CLEO/Europe-EQEC Conference, 2009, paper CJ7.1.

Silvestri, S. D.

Simpson, N. B.

Sowa, S.

Spilman, A. K.

A. K. Spilman and T. G. Brown, “Stress birefringent, space-variant wave plates for vortex illumination,” Appl. Optics 46, 61–66 (2007).
[CrossRef]

Stoian, R.

Sugahara, T.

P. G. Eliseev, S. Juodkazis, T. Sugahara, H.-B. Sun, S. Matsuo, S. Sakai, and H. Misawa, “GaN surface ablation by fs-pulses: atomic force microscopy studies, accumulation effects,” in Proceedings of High-Power Laser Ablation Conf. (SPIE Proc. 4065, 2000) pp.546–556.

Sun, H.-B.

P. G. Eliseev, S. Juodkazis, T. Sugahara, H.-B. Sun, S. Matsuo, S. Sakai, and H. Misawa, “GaN surface ablation by fs-pulses: atomic force microscopy studies, accumulation effects,” in Proceedings of High-Power Laser Ablation Conf. (SPIE Proc. 4065, 2000) pp.546–556.

Sundaram, S. K.

S. K. Sundaram and E. Mazur, “Inducing and probing non-thermal transitions in semiconductors using femtosecond laser pulses,” Nature Mat. 1, 217–224 (2002).
[CrossRef]

Surovtsev, N. V.

V. Mizeikis, S. Kimura, N. V. Surovtsev, V. Jarutis, A. Saito, H. Misawa, and S. Juodkazis, “Formation of amorphous sapphire by a femtosecond-pulse-induced micro-explosion,” Appl. Surf. Sci. 255, 9745–9749 (2009).
[CrossRef]

Swartzlander, G. A.

Syassen, K.

K. Syassen, “Ruby under pressure,” High Pressure Research 28, 75–126 (2008).
[CrossRef]

Taccheo, S.

Takahashi, J.-I.

J. Morikawa, C. Leong, T. Hashimoto, T. Ogawa, Y. Urata, S. Wada, M. Higuchi, and J.-I. Takahashi, “Thermal conductivity/diffusivity of Nd3+ doped GdVO4, YVO4, LuVO4,and Y3Al5O12 by temperature wave analysis,” J. Appl. Phys. 103, 063522 (2008).
[CrossRef]

Takahashi, T.

S. Juodkazis, M. Shikata, T. Takahashi, S. Matsuo, and H. Misawa, “Fast optical swithing by a laser manipulated microdroplet of liquid crystal,” Appl. Phys. Lett. 74, 3627–3629 (1999).
[CrossRef]

Tamaki, T.

Tanaka, S.

S. Juodkazis, K. Nishimura, S. Tanaka, H. Misawa, E. E. Gamaly, B. Luther-Davies, L. Hallo, P. Nicolai, and V. Tikhonchuk, “Laser-induced microexplosion confined in the bulk of a sapphire crystal: Evidence of multimegabar pressures,” Phys. Rev. Lett. 96, 166101 (2006).
[CrossRef] [PubMed]

Tapster, P. R.

M. Harris, C. A. Hill, P. R. Tapster, and J. M. Vaughan, “Laser modes with helical wave fronts,” Phys. Rev. A 49, 3119–3122 (1994).
[CrossRef] [PubMed]

Tikhonchuk, V.

S. Juodkazis, K. Nishimura, S. Tanaka, H. Misawa, E. E. Gamaly, B. Luther-Davies, L. Hallo, P. Nicolai, and V. Tikhonchuk, “Laser-induced microexplosion confined in the bulk of a sapphire crystal: Evidence of multimegabar pressures,” Phys. Rev. Lett. 96, 166101 (2006).
[CrossRef] [PubMed]

E. E. Gamaly, S. Juodkazis, K. Nishimura, H. Misawa, B. Luther-Davies, L. Hallo, P. Nicolai, and V. Tikhonchuk, “Laser-matter interaction in a bulk of a transparent solid: confined micro-explosion and void formation,” Phys. Rev. B 73, 214101 (2006).
[CrossRef]

Tomasiunas, R.

M. Beresna, T. Gertus, R. Tomasiunas, H. Misawa, and S. Juodkazis, “Three-dimensional modeling of the heat-affected zone in laser machining applications,” Laser Chemistry 2008, 976205 (2008).
[CrossRef]

Tünnermann, A.

S. Nolte, M. Will, J. Burghoff, and A. Tünnermann, “Femtosecond waveguide writing: a new avenue to three-dimensional integrated optics,” Appl. Phys. A 77, 109–111 (2003).
[CrossRef]

Tünnermann, S. N. A.

J. Siebenmorgen, K. Petermann, G. Huber, K. Rademaker, and S. N. A. Tünnermann, “Femtosecond laser written stress-induced Nd:Y3Al5O12(Nd:YAG) channel waveguide laser,” Appl. Phys. B 97, 251–255 (2009).
[CrossRef]

Tuzhilin, D.

E. Vanagas, I. Kudryashov, D. Tuzhilin, S. Juodkazis, S. Matsuo, and H. Misawa, “Surface nanostructuring of borosilicate glass by femtosecond nJ energy pulses,” Appl. Phys. Lett. 82, 2901–2903 (2003).
[CrossRef]

Ueno, K.

K. Ueno, S. Juodkazis, T. Shibuya, V. Mizeikis, Y. Yokota, and H. Misawa, “Nano-particle-enhanced photo-polymerization,” J. Phys. Chem. C 113, 11720–11724 (2009).
[CrossRef]

Urata, Y.

J. Morikawa, C. Leong, T. Hashimoto, T. Ogawa, Y. Urata, S. Wada, M. Higuchi, and J.-I. Takahashi, “Thermal conductivity/diffusivity of Nd3+ doped GdVO4, YVO4, LuVO4,and Y3Al5O12 by temperature wave analysis,” J. Appl. Phys. 103, 063522 (2008).
[CrossRef]

Vanagas, E.

E. Vanagas, I. Kudryashov, D. Tuzhilin, S. Juodkazis, S. Matsuo, and H. Misawa, “Surface nanostructuring of borosilicate glass by femtosecond nJ energy pulses,” Appl. Phys. Lett. 82, 2901–2903 (2003).
[CrossRef]

Vaughan, J. M.

M. Harris, C. A. Hill, P. R. Tapster, and J. M. Vaughan, “Laser modes with helical wave fronts,” Phys. Rev. A 49, 3119–3122 (1994).
[CrossRef] [PubMed]

Vedam, K.

T. A. Davis and K. Vedam, “Photoelastic properties of sapphire (α - Al2O3),” J. Appl. Phys. 38, 4556–4557 (1967).

Wada, S.

J. Morikawa, C. Leong, T. Hashimoto, T. Ogawa, Y. Urata, S. Wada, M. Higuchi, and J.-I. Takahashi, “Thermal conductivity/diffusivity of Nd3+ doped GdVO4, YVO4, LuVO4,and Y3Al5O12 by temperature wave analysis,” J. Appl. Phys. 103, 063522 (2008).
[CrossRef]

Waki, R.

S. Juodkazis, K. Nishimura, H. Misawa, T. Ebisui, R. Waki, S. Matsuo, and T. Okada, “Control over the state of crystallinity: Sapphire,” Adv. Mat. 18, 1361–1364 (2006).
[CrossRef]

Watanabe, W.

Will, M.

S. Nolte, M. Will, J. Burghoff, and A. Tünnermann, “Femtosecond waveguide writing: a new avenue to three-dimensional integrated optics,” Appl. Phys. A 77, 109–111 (2003).
[CrossRef]

Williams, P. A.

Winey, J. M.

J. M. Winey, Y. M. Gupta, and D. E. Hare, “r-axis sound speed and elastic properties of sapphire single crystals,” J. Appl. Phys. 90, 3109–3111 (2001).
[CrossRef]

Withford, M. J.

M. Ams, G. D. Marshall, P. Dekker, J. A. Piper, and M. J. Withford, “Ultrafast laser written active devices,” Laser Photon. Rev. 3, 535–544 (2009).
[CrossRef]

Wu, J.

M. J. Assael, K. D. Antoniadis, and J. Wu, “New measurements of the thermal conductivity of PMMA, BK7, and Pyrex 7740 up to 450K,” Int. J. Thermophys. 292, 1257–1266 (2008).
[CrossRef]

Yamasaki, K.

S. Juodkazis, K. Yamasaki, V. Mizeikis, S. Matsuo, and H. Misawa, “Formation of embedded patterns in glasses using femtosecond irradiation,” Appl. Phys. A 79, 1549–1553 (2004).
[CrossRef]

Yokota, Y.

K. Ueno, S. Juodkazis, T. Shibuya, V. Mizeikis, Y. Yokota, and H. Misawa, “Nano-particle-enhanced photo-polymerization,” J. Phys. Chem. C 113, 11720–11724 (2009).
[CrossRef]

Zhang, H.

Zhu, Z.

Adv. Func. Mat. (1)

Y. Lan, A. J. Minnich, G. Chen, and Z. Ren, “Enhancement of thermoelectric figure-of-merit by a bulk nanostructuring approach,” Adv. Func. Mat.,  20, 357–376 (2010).
[CrossRef]

Adv. Mat. (1)

S. Juodkazis, K. Nishimura, H. Misawa, T. Ebisui, R. Waki, S. Matsuo, and T. Okada, “Control over the state of crystallinity: Sapphire,” Adv. Mat. 18, 1361–1364 (2006).
[CrossRef]

Appl. Opt. (2)

Appl. Optics (1)

A. K. Spilman and T. G. Brown, “Stress birefringent, space-variant wave plates for vortex illumination,” Appl. Optics 46, 61–66 (2007).
[CrossRef]

Appl. Phys. A (3)

T. Hashimoto, S. Juodkazis, and H. Misawa, “Void recording in silica,” Appl. Phys. A 83, 337–340 (2006).
[CrossRef]

S. Nolte, M. Will, J. Burghoff, and A. Tünnermann, “Femtosecond waveguide writing: a new avenue to three-dimensional integrated optics,” Appl. Phys. A 77, 109–111 (2003).
[CrossRef]

S. Juodkazis, K. Yamasaki, V. Mizeikis, S. Matsuo, and H. Misawa, “Formation of embedded patterns in glasses using femtosecond irradiation,” Appl. Phys. A 79, 1549–1553 (2004).
[CrossRef]

Appl. Phys. A. (2)

A. Marcinkevicius, V. Mizeikis, S. Juodkazis, S. Matsuo, and H. Misawa, “Effect of refractive index-mismatch on laser microfabrication in silica glass,” Appl. Phys. A. 76, 257–260 (2003).
[CrossRef]

J. Morikawa, A. Orie, T. Hashimoto, and S. Juodkazis, “Thermal diffusivity in femtosecond-laser-structured micro-volumes of polymers,” Appl. Phys. A. 98, 551–556 (2010).
[CrossRef]

Appl. Phys. B (1)

J. Siebenmorgen, K. Petermann, G. Huber, K. Rademaker, and S. N. A. Tünnermann, “Femtosecond laser written stress-induced Nd:Y3Al5O12(Nd:YAG) channel waveguide laser,” Appl. Phys. B 97, 251–255 (2009).
[CrossRef]

Appl. Phys. Lett. (4)

Y. Bellouard, M. Dugan, A. A. Said, and P. Bado, “Thermal conductivity contrast measurement of fused silica exposed to low-energy femtosecond laser pulses,” Appl. Phys. Lett. 89, 161911 (2006).
[CrossRef]

E. Vanagas, I. Kudryashov, D. Tuzhilin, S. Juodkazis, S. Matsuo, and H. Misawa, “Surface nanostructuring of borosilicate glass by femtosecond nJ energy pulses,” Appl. Phys. Lett. 82, 2901–2903 (2003).
[CrossRef]

S. Juodkazis, M. Shikata, T. Takahashi, S. Matsuo, and H. Misawa, “Fast optical swithing by a laser manipulated microdroplet of liquid crystal,” Appl. Phys. Lett. 74, 3627–3629 (1999).
[CrossRef]

S. Juodkazis, S. Matsuo, N. Murazawa, I. Hasegawa, and H. Misawa, “High-efficiency optical transfer of torque to a nematic liquid crystal,” Appl. Phys. Lett. 82, 4657–4659 (2003).
[CrossRef]

Appl. Surf. Sci. (1)

V. Mizeikis, S. Kimura, N. V. Surovtsev, V. Jarutis, A. Saito, H. Misawa, and S. Juodkazis, “Formation of amorphous sapphire by a femtosecond-pulse-induced micro-explosion,” Appl. Surf. Sci. 255, 9745–9749 (2009).
[CrossRef]

High Pressure Research (1)

K. Syassen, “Ruby under pressure,” High Pressure Research 28, 75–126 (2008).
[CrossRef]

Int. J. Sol. Struct. (1)

J. W. Kysar, “Path of light in near crack tip region in anisotropic medium and under mixed-mode loading,” Int. J. Sol. Struct. 38, 5963–5973 (2001).
[CrossRef]

Int. J. Thermophys. (1)

M. J. Assael, K. D. Antoniadis, and J. Wu, “New measurements of the thermal conductivity of PMMA, BK7, and Pyrex 7740 up to 450K,” Int. J. Thermophys. 292, 1257–1266 (2008).
[CrossRef]

J. Appl. Phys. (6)

J. Morikawa, C. Leong, T. Hashimoto, T. Ogawa, Y. Urata, S. Wada, M. Higuchi, and J.-I. Takahashi, “Thermal conductivity/diffusivity of Nd3+ doped GdVO4, YVO4, LuVO4,and Y3Al5O12 by temperature wave analysis,” J. Appl. Phys. 103, 063522 (2008).
[CrossRef]

J. Morikawa and T. Hashimoto, “Thermal diffusivity of aromatic polyimide thin films by temperature wave analysis,” J. Appl. Phys. 105, 113506 (2009).
[CrossRef]

S. Juodkazis, V. Mizeikis, and H. Misawa, “Three-dimensional microfabrication of materials by femtosecond lasers for photonics applications,” J. Appl. Phys. 106, 051101 (2009).
[CrossRef]

J. Reintjes and M. B. Schulz, “Photoelastic constants of selected ultrasonic delay-line crystals,” J. Appl. Phys. 39, 5254–5258 (1968).
[CrossRef]

J. M. Winey, Y. M. Gupta, and D. E. Hare, “r-axis sound speed and elastic properties of sapphire single crystals,” J. Appl. Phys. 90, 3109–3111 (2001).
[CrossRef]

T. A. Davis and K. Vedam, “Photoelastic properties of sapphire (α - Al2O3),” J. Appl. Phys. 38, 4556–4557 (1967).

J. Non-Cryst. Sol. (1)

D. M. Krol, “Femtosecond laser modification of glass,” J. Non-Cryst. Sol. 354, 416–424 (2009).
[CrossRef]

J. Phys. Chem. C (1)

K. Ueno, S. Juodkazis, T. Shibuya, V. Mizeikis, Y. Yokota, and H. Misawa, “Nano-particle-enhanced photo-polymerization,” J. Phys. Chem. C 113, 11720–11724 (2009).
[CrossRef]

Laser Chemistry (1)

M. Beresna, T. Gertus, R. Tomasiunas, H. Misawa, and S. Juodkazis, “Three-dimensional modeling of the heat-affected zone in laser machining applications,” Laser Chemistry 2008, 976205 (2008).
[CrossRef]

Laser Photon. Rev. (1)

M. Ams, G. D. Marshall, P. Dekker, J. A. Piper, and M. J. Withford, “Ultrafast laser written active devices,” Laser Photon. Rev. 3, 535–544 (2009).
[CrossRef]

Nature (2)

M. Berry, “Making waves in physics,” Nature 403, 21 (2000).
[CrossRef] [PubMed]

M. E. J. Friese, T. A. Nieminen, N. R. Heckenberg, and H. Rubinsztein-Dunlop, “Optical alignment and spinning of laser-trapped microscopic particles,” Nature 394, 348–350 (1998).
[CrossRef]

Nature Mat. (1)

S. K. Sundaram and E. Mazur, “Inducing and probing non-thermal transitions in semiconductors using femtosecond laser pulses,” Nature Mat. 1, 217–224 (2002).
[CrossRef]

Opt. Express (6)

Opt. Lett. (6)

Phys. Rev. A (1)

M. Harris, C. A. Hill, P. R. Tapster, and J. M. Vaughan, “Laser modes with helical wave fronts,” Phys. Rev. A 49, 3119–3122 (1994).
[CrossRef] [PubMed]

Phys. Rev. B (1)

E. E. Gamaly, S. Juodkazis, K. Nishimura, H. Misawa, B. Luther-Davies, L. Hallo, P. Nicolai, and V. Tikhonchuk, “Laser-matter interaction in a bulk of a transparent solid: confined micro-explosion and void formation,” Phys. Rev. B 73, 214101 (2006).
[CrossRef]

Phys. Rev. E (1)

A. Ciattoni, G. Cincotti, and C. Palma, “Angular momentum dynamics of a paraxial beam in a uniaxial crystal,” Phys. Rev. E 67, 036618 (2003).
[CrossRef]

Phys. Rev. Lett. (4)

L. Marrucci, C. Manzo, and D. Paparo, “Optical spin-to-orbital angular momentum conversion in inhomogeneous anisotropic media,” Phys. Rev. Lett. 96, 163905 (2006).
[CrossRef] [PubMed]

H. He, M. E. J. Friese, N. R. Heckenberg, and H. Rubinsztein-Dunlop, “Direct observation of transfer of angular-momentum to absorptive particles from a laser-beam with a phase singularity,” Phys. Rev. Lett. 75, 826–829 (1995).
[CrossRef] [PubMed]

S. Juodkazis, K. Nishimura, S. Tanaka, H. Misawa, E. E. Gamaly, B. Luther-Davies, L. Hallo, P. Nicolai, and V. Tikhonchuk, “Laser-induced microexplosion confined in the bulk of a sapphire crystal: Evidence of multimegabar pressures,” Phys. Rev. Lett. 96, 166101 (2006).
[CrossRef] [PubMed]

E. Brasselet, N. Murazawa, H. Misawa, and S. Juodkazis, “Optical vortices from liquid crystal droplets,” Phys. Rev. Lett. 103, 103903 (2009).
[CrossRef] [PubMed]

Prog. Polym. Sci. (1)

H. Misawa and S. Juodkazis, “Photophysics and photochemistry of a laser manipulated microparticle,” Prog. Polym. Sci. 24, 665–697 (1999).
[CrossRef]

Progress in Optics (1)

L. Allen, M. J. Padgett, and M. Babiker, “The orbital angular momentum of light,” Progress in Optics 39, 291–372 (1999).
[CrossRef]

Other (6)

J. Siebenmorgen, T. Calmano, O. Hellmig, K. Petermann, and G. Huber, “Efficient femtosecond laser written Nd:YAG channel waveguide laser with an output power of more than 1 W,”, Technical Digest, CLEO/Europe-EQEC Conference, 2009, paper CJ7.1.

H. Aben, Photoelasticity of glass (Springer-Verlag Berlin, 1993).

“http://en.wikipedia.org/wiki/Hooke’s_law.”

P. G. Eliseev, S. Juodkazis, T. Sugahara, H.-B. Sun, S. Matsuo, S. Sakai, and H. Misawa, “GaN surface ablation by fs-pulses: atomic force microscopy studies, accumulation effects,” in Proceedings of High-Power Laser Ablation Conf. (SPIE Proc. 4065, 2000) pp.546–556.

R. A. L. Jones, Soft Condensed Matter (Oxford University Press, 2002).

B. Rogers, S. Pennathur, and J. Adams, Nanotechnology: understanding small systems (CRC Press Taylor and Francis Group, Boca Raton, 2008).

Supplementary Material (1)

» Media 1: PDF (295 KB)     

Cited By

OSA participates in CrossRef's Cited-By Linking service. Citing articles from OSA journals and other participating publishers are listed here.

Alert me when this article is cited.


Figures (4)

Fig. 1.
Fig. 1.

(a) Al2O3 wafer padded with sputtered Au and Al electrodes used for thermal diffusivity measurements with a close up polariscope view (b) of the laser-structured volume. The sensor (S) and reference (host) positions are marked, respectively. Inset in (b) shows simulated transmission profile according to eqn. 3; the transmission pattern is orientated in the same way as in actual experiments. (c) Schematics of the thermal wave propagation from the heater (on bottom) towards the hot-junction sensor (on top); not to scale. See, the experimental section for details.

Fig. 2.
Fig. 2.

(a) Normalized thermal diffusivity, χShost, (see, Fig. 1(b)) through the laser-structured (1), adjacent (3) regions vs number of measurement cycles. Error bars are 2%. (b) Polariscope image shows a region laser-structured by 80 nJ/pulse energy with two pulse per irradiation site. An approximate location and size of the hot-junction sensors are marked. Inset shows a slanted view of the computer generated 3D pattern of the irradiation spots (circles) and the movement path (lines).

Fig. 3.
Fig. 3.

Polariscopy data. (a) The amplitude, i.e., retardance distribution ( Γ ( x , y ) / 2 π × λ 0 ) [nm] on a c-plane of sapphire sample with a fs-laser structured region of 30 μm in diameter at the center (as shown in Fig. 2(b)). (b) The azimuth or distribution of the slow axis orientation, Ψ(x,y). The arrows are pointing to location of a pair of topological phase defects where birefringence and the orientation of the polarization ellipsis are undefined. Scale, radians. (c) Horizontal and diagonal cross-sections of the birefringence, Δn(x, y), map given in (a); calculated from experimentally measured retardance Γ(x, y)/2 = π λ 0 Δn(x,y)d (λ0 = 546 nm, d ≃ 90 μm). The exponential 1/e fits with a birefringence (stress) relaxation constant τR = 24 μm are shown as eye guides. Red and grey marked regions indicate the laser structured locations. Pulse energy was 80 nJ/pulse. Stress-induced crack formation is demonstrated at the corners of volume with a square footprint (Media 1); this proves a stress-related origin of the birefringence rather than form-birefringence.

Fig. 4.
Fig. 4.

(a) The azimuth, Ψ(x, y), (grey scale map 0-π) map around two regions of smaller Δnmax ≃ 10-3) (1) and by 50% larger (2) birefringence; the dial-markers shows the orientation of the azimuth; pulse energies were 80 (1) and 120 nJ/pulse (2), respectively. The central laser structured regions have the same 30 μm diameters (marked by circles). (b) Close up view of the central part of region (1) with two singularities of azimuthal orientation of the polarization ellipsis. A round trip phase changes by π for the two singularities (marked by arrows).

Equations (3)

Equations on this page are rendered with MathJax. Learn more.

Δ θ = π f χ d θ 0 ,
k c = ρ c p v Λ / 3 ,
I t ( φ , Δ n ) = I 0 sin 2 ( 2 φ ) sin 2 ( Γ/ 2 )

Metrics