Abstract

We propose to induce a two-dimensional (2D) periodic modulation structure into a planar Grandjean cholesteric liquid crystal (CLC) to demonstrate the intrinsic 2D photonic crystal properties of such materials. The structure combines a thin transmission grating and a Bragg reflective grating. One advantage of using CLC is the intrinsic high quality Bragg structure, which can be modulated by an electric field: shifting the wavelength band edge by changing the applied field. Another interesting property is the polarization dependence. The main difference between using CLC Bragg instead of a linear grating is the need to operate with a circularly polarized light, because the CLC modes are circular in such a regime. We present preliminary results obtained with what we believe to be the first switchable photonic CLC (PCLC) sample, made up of a polymer CLC gel.

© 2007 Optical Society of America

Full Article  |  PDF Article

References

  • View by:
  • |
  • |

  1. P. Gravey, J. L. de Bougrenet de la Tocnaye, B. Fracasso, N. Wolffer, A. Tan, B. Vinouze, and M. Razzak, "Liquid crsytal based optical space switches for DWDM networks," Ann. Telecommun. 58, 1378-1400 (2003).
  2. D. Subacius, Ph. Bos, and O. D. Lavrentovich, "Switchable diffractive cholesteric gratings," Appl. Phys. Lett. 17, 1350-1353 (1997).
    [CrossRef]
  3. B. I. Senyuk, I. I. Smalyukh, and O. D. Lavrentovitch, "Switchable 2D gratings based on field induced layer undulations in CLC," Opt. Lett. 30, 349-351 (2005).
    [CrossRef] [PubMed]
  4. Q. He, I. Zaquine, A. Maruani, S. Massenot, R. Chevallier, and R. Frey, "Band-edge-induced Bragg diffraction in 2D photonic crystals," Opt. Lett. 31, 1184-1186 (2006).
    [CrossRef] [PubMed]
  5. P. Yeh and C. Gu, Optics of Liquid Crystal Display (Wiley, 1999).
  6. Q. Li, L. Li, J. Kim, H. S. Park, and J. Williams, "Reversible photoresponsive chiral LC containing Cholesteryl moiety and Azobenzene linker," Chem. Mater 17, 6018-6021 (2005).
    [CrossRef]
  7. V. Sergan, Y. Reznikov, J. Anderson, P. Watson, J. Ruth, and P. Bos, "Mechanism of relaxation from electric field induced homeotropic to planar texture in cholesteric liquid crystals," Mol. Cryst. Liq. Cryst. 330, 1339-1344 (1999).
    [CrossRef]
  8. D. K. Hwang and A. D. Rey, "Computational studies of optical textures of twist disclination loops in liquid-crystal films by using the finite-difference time-domain method," J. Opt. Soc. Am. A 23, 483-496 (2006).
    [CrossRef]
  9. Q. Wang, G. Farrell, and Y. Semenova, "Modeling liquid-crystal devices with the three-dimensional full-vector beam propagation method," J. Opt. Soc. Am. A 23, 2014-2019 (2006).
    [CrossRef]
  10. J. M. Bendickson, J. P. Dowling, and M. Scalora, "Analytic expressions for the electromagnetic mode density in finite 1D photonic band-gap structure," Phys. Rev. 53, 4107-4121 (1996).
  11. B. Meziane, C. Li, P. Carette, and M. Warenghem, "Performance of a polymer CLC output coupler in Nd-doped fiber lasers," Opt. Express 10, 965-967 (2002).
    [PubMed]
  12. Z. Zalevsky, F. Luan, W. J. Wadsworth, S. L. Saval, and T. A. Birks, "Liquid-crystal-based in-fiber tunable spectral structures," Opt. Eng. 45, 035005 (2006).
    [CrossRef]
  13. S. C. Chou, L. Cheung, and R. B. Meyer, "Effects of a magnetic field on the optical transmission in CLC," Solid State Commun. 11, 977-981 (1972).
    [CrossRef]

2006 (4)

2005 (2)

B. I. Senyuk, I. I. Smalyukh, and O. D. Lavrentovitch, "Switchable 2D gratings based on field induced layer undulations in CLC," Opt. Lett. 30, 349-351 (2005).
[CrossRef] [PubMed]

Q. Li, L. Li, J. Kim, H. S. Park, and J. Williams, "Reversible photoresponsive chiral LC containing Cholesteryl moiety and Azobenzene linker," Chem. Mater 17, 6018-6021 (2005).
[CrossRef]

2003 (1)

P. Gravey, J. L. de Bougrenet de la Tocnaye, B. Fracasso, N. Wolffer, A. Tan, B. Vinouze, and M. Razzak, "Liquid crsytal based optical space switches for DWDM networks," Ann. Telecommun. 58, 1378-1400 (2003).

2002 (1)

1999 (1)

V. Sergan, Y. Reznikov, J. Anderson, P. Watson, J. Ruth, and P. Bos, "Mechanism of relaxation from electric field induced homeotropic to planar texture in cholesteric liquid crystals," Mol. Cryst. Liq. Cryst. 330, 1339-1344 (1999).
[CrossRef]

1997 (1)

D. Subacius, Ph. Bos, and O. D. Lavrentovich, "Switchable diffractive cholesteric gratings," Appl. Phys. Lett. 17, 1350-1353 (1997).
[CrossRef]

1996 (1)

J. M. Bendickson, J. P. Dowling, and M. Scalora, "Analytic expressions for the electromagnetic mode density in finite 1D photonic band-gap structure," Phys. Rev. 53, 4107-4121 (1996).

1972 (1)

S. C. Chou, L. Cheung, and R. B. Meyer, "Effects of a magnetic field on the optical transmission in CLC," Solid State Commun. 11, 977-981 (1972).
[CrossRef]

Ann. Telecommun. (1)

P. Gravey, J. L. de Bougrenet de la Tocnaye, B. Fracasso, N. Wolffer, A. Tan, B. Vinouze, and M. Razzak, "Liquid crsytal based optical space switches for DWDM networks," Ann. Telecommun. 58, 1378-1400 (2003).

Appl. Phys. Lett. (1)

D. Subacius, Ph. Bos, and O. D. Lavrentovich, "Switchable diffractive cholesteric gratings," Appl. Phys. Lett. 17, 1350-1353 (1997).
[CrossRef]

Chem. Mater (1)

Q. Li, L. Li, J. Kim, H. S. Park, and J. Williams, "Reversible photoresponsive chiral LC containing Cholesteryl moiety and Azobenzene linker," Chem. Mater 17, 6018-6021 (2005).
[CrossRef]

J. Opt. Soc. Am. A (2)

Mol. Cryst. Liq. Cryst. (1)

V. Sergan, Y. Reznikov, J. Anderson, P. Watson, J. Ruth, and P. Bos, "Mechanism of relaxation from electric field induced homeotropic to planar texture in cholesteric liquid crystals," Mol. Cryst. Liq. Cryst. 330, 1339-1344 (1999).
[CrossRef]

Opt. Eng. (1)

Z. Zalevsky, F. Luan, W. J. Wadsworth, S. L. Saval, and T. A. Birks, "Liquid-crystal-based in-fiber tunable spectral structures," Opt. Eng. 45, 035005 (2006).
[CrossRef]

Opt. Express (1)

Opt. Lett. (2)

Phys. Rev. (1)

J. M. Bendickson, J. P. Dowling, and M. Scalora, "Analytic expressions for the electromagnetic mode density in finite 1D photonic band-gap structure," Phys. Rev. 53, 4107-4121 (1996).

Solid State Commun. (1)

S. C. Chou, L. Cheung, and R. B. Meyer, "Effects of a magnetic field on the optical transmission in CLC," Solid State Commun. 11, 977-981 (1972).
[CrossRef]

Other (1)

P. Yeh and C. Gu, Optics of Liquid Crystal Display (Wiley, 1999).

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 (13)

Fig. 1
Fig. 1

CLC typical bandgap and cutoff frequencies for various pitch numbers.

Fig. 2
Fig. 2

30   μm CLC sample. Spectrum measured in a planar configuration before applying voltage, and after the relaxation into a focal conic state. The bottom curve corresponds to the focal conic state, with reduced transmission due to scattering.

Fig. 3
Fig. 3

Polymer stabilized CLC: black curve, no applied voltage; black dashed, with voltage values of about 2   V / μm ; gray curve, at the voltage saturation close to 5 V / μm .

Fig. 4
Fig. 4

Circularly polarized light transmission for a 30   μm sample. Gray curve, a 7° incidence angle; black curve, a 14° incidence angle. We observed oscillations near the band edge.

Fig. 5
Fig. 5

Transmission responses of the PSCLC (polymer stabilized CLC) as a function of the polarization. Each sector corresponds to 10°.

Fig. 6
Fig. 6

Measurement of the response time of polymer stabilized CLC (top curve). The bottom gray curve is the applied voltage.

Fig. 7
Fig. 7

Principle of the 2D photonic crystal by a 2D sinusoidal modulation of the refractive index.

Fig. 8
Fig. 8

Principle of the switchable PCLC device.

Fig. 9
Fig. 9

Schematic of the measurement setup.

Fig. 10
Fig. 10

First diffracted order spectrum ( 30   μm grating period). Bottom two curves for low applied voltages: 0 .25   V / μm and orthogonal polarizations RCP and LCP (no change in intensity for LCP). Top two curves for larger applied voltage 2 V / μm , and orthogonal polarizations RCP and LCP (once again for LCP, no visible wavelength dependence, apart from the random noise).

Fig. 11
Fig. 11

Diffracted order spectra, ( 30   μm grating period). Applied voltage changes: from bottom to top (following the left part of the figure): 0 .25   V / μm , 1 V / μm , 5 V / μm , 3 V / μm .

Fig. 12
Fig. 12

Diffracted order spectra for PCLC with different grating periods and the same applied voltage ( 0.25 V / μm ) . Thin black curve (first sharp peak is not fully shown) corresponds to 30 μm grating, thick black curve to the 15 μm and thick gray curve corresponds to the 8 μm.

Fig. 13
Fig. 13

Diffracted order polarization dependence: Gray curve ( 1 ) , black ( + 1 ) . Input polarizations vary from LHC (sector 2) to a RHC (sector 6). Each sector corresponds to 20°.

Equations (6)

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

n o P < λ < n e P ,
Δ λ = Δ n P .
n ( x , y ) = n 0 + Δ n X cos ( 2 π x Λ X ) + Δ n Y cos ( 2 π y Λ Y ) ,
sin θ B = λ R 2 n Λ X ,
I + 1 I 1 = sin c 2 ( π λ R L n Λ X 2 ) ,
Q = π λ R L n Λ X 2 .

Metrics