Abstract

We report on successful joining of a beta barium borate crystal by plasma-activated direct bonding. Based on this technology, a sandwich structure consisting of a beta barium borate crystal, joined with two sapphire heat spreaders has been fabricated. Due to the high thermal conductivity of sapphire, the sandwich structure possesses superior thermal properties compared to the single crystal. Simulations based on the finite element method indicate a significant reduction of thermal gradients and the resulting mechanical stresses. A proof of principle experiment demonstrates the high power capability of the fabricated structure. A pulsed fiber laser emitting up to 253 W average power has been frequency doubled with both a single BBO crystal and the fabricated sandwich structure. The bonded stack showed better heat dissipation and less thermo-optical beam distortion than the single crystal. The work demonstrates the huge potential of optical sandwich structures with enhanced functionality. In particular, frequency conversion at average powers in the kW range with excellent beam quality will be feasible in future.

© 2014 Optical Society of America

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References

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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef] [PubMed]
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    [CrossRef]
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    [CrossRef]
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  14. A. Smith, “SNLO,” http://www.as-photonics.com/snlo .
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef] [PubMed]
  22. F. Jansen, F. Stutzki, H. Otto, T. Eidam, A. Liem, C. Jauregui, J. Limpert, and A. Tünnermann, “Thermally induced waveguide changes in active fibers,” Opt. Express20, 3997–4008 (2012).
  23. R. Riedel, J. Rothhardt, K. Beil, B. Gronloh, A. Klenke, H. Höppner, M. Schulz, U. Teubner, C. Kränkel, J. Limpert, A. Tünnermann, M. J. Prandolini, and F. Tavella, “Thermal properties of borate crystals for high power optical parametric chirped-pulse amplification,” Opt. Express (submitted to).
  24. S. Kaplan and L. Hanssen, “Normal infrared spectral emittance of Al203,” in Optical Diagnostic Methods for Inorganic Transmissive Materials (SPIE, 1998), Vol. 3425, pp. 120–125.
  25. P. Baum, D. Charalambidis, J. A. Fülöp, U. Kleineberg, F. Krausz, G. Szabó, G. Tsakiris, K. Varjú, L. Veisz, and M. Vrakking, “The Attosecond Light Pulse Source (ALPS) of the Extreme Light Infrastructure (ELI),” http://www.eli-hu.hu/uploads/File/Ceges_doksik_2013/Science/ELI_ALPS_Science_and_Technology.pdf .

2013 (2)

2012 (2)

2008 (1)

2006 (1)

A. Dubietis, R. Butkus, and A. P. Piskarskas, “Trends in chirped pulse optical parametric amplification,” IEEE J. Sel. Top. Quantum Electron.12(2), 163–172 (2006).
[CrossRef]

2003 (1)

G. Cerullo and S. De Silvestri, “Ultrafast optical parametric amplifiers,” Rev. Sci. Instrum.74(1), 1 (2003).
[CrossRef]

1998 (1)

U. Gösele and Q. Tong, “Semiconductor wafer bonding,” Annu. Rev. Mater. Sci.28(1), 215–241 (1998).
[CrossRef]

1991 (1)

D. N. Nikogosyan, “Beta Barium Borate (BBO): a review of its properties and applications,” Appl. Phys. A368, 359-368 (1991).

1990 (1)

D. Eimerl, S. Velsko, L. Davis, and F. Wang, “Progress in nonlinear optical materials for high power lasers,” Prog. Cryst. Growth Charact. Mater.20(1-2), 59–113 (1990).
[CrossRef]

1988 (1)

L. Bromley, A. Guy, and D. Hanna, “Synchronously pumped optical parametric oscillation in beta-barium borate,” Opt. Commun.67(4), 3–7 (1988).
[CrossRef]

1987 (1)

D. Eimerl, L. Davis, S. Velsko, E. K. Graham, and A. Zalkin, “Optical, mechanical, and thermal properties of barium borate,” J. Appl. Phys.62(5), 1968 (1987).
[CrossRef]

1981 (1)

M. Iwasa, T. Ueno, and R. C. Bradt, “Fracture Toughness of Quartz and Sapphire Single Crystals at Room Temperature,” Zairyo30(337), 1001–1004 (1981).
[CrossRef]

1960 (1)

T. Maiman, “Stimulated optical radiation in ruby,” Nature187(4736), 493–494 (1960).
[CrossRef]

Beil, K.

R. Riedel, J. Rothhardt, K. Beil, B. Gronloh, A. Klenke, H. Höppner, M. Schulz, U. Teubner, C. Kränkel, J. Limpert, A. Tünnermann, M. J. Prandolini, and F. Tavella, “Thermal properties of borate crystals for high power optical parametric chirped-pulse amplification,” Opt. Express (submitted to).

Bradt, R. C.

M. Iwasa, T. Ueno, and R. C. Bradt, “Fracture Toughness of Quartz and Sapphire Single Crystals at Room Temperature,” Zairyo30(337), 1001–1004 (1981).
[CrossRef]

Breitkopf, S.

Bromley, L.

L. Bromley, A. Guy, and D. Hanna, “Synchronously pumped optical parametric oscillation in beta-barium borate,” Opt. Commun.67(4), 3–7 (1988).
[CrossRef]

Butkus, R.

A. Dubietis, R. Butkus, and A. P. Piskarskas, “Trends in chirped pulse optical parametric amplification,” IEEE J. Sel. Top. Quantum Electron.12(2), 163–172 (2006).
[CrossRef]

Cerullo, G.

G. Cerullo and S. De Silvestri, “Ultrafast optical parametric amplifiers,” Rev. Sci. Instrum.74(1), 1 (2003).
[CrossRef]

Chiang, A. C.

Davis, L.

D. Eimerl, S. Velsko, L. Davis, and F. Wang, “Progress in nonlinear optical materials for high power lasers,” Prog. Cryst. Growth Charact. Mater.20(1-2), 59–113 (1990).
[CrossRef]

D. Eimerl, L. Davis, S. Velsko, E. K. Graham, and A. Zalkin, “Optical, mechanical, and thermal properties of barium borate,” J. Appl. Phys.62(5), 1968 (1987).
[CrossRef]

De Silvestri, S.

G. Cerullo and S. De Silvestri, “Ultrafast optical parametric amplifiers,” Rev. Sci. Instrum.74(1), 1 (2003).
[CrossRef]

Demmler, S.

Dubietis, A.

A. Dubietis, R. Butkus, and A. P. Piskarskas, “Trends in chirped pulse optical parametric amplification,” IEEE J. Sel. Top. Quantum Electron.12(2), 163–172 (2006).
[CrossRef]

Eidam, T.

Eimerl, D.

D. Eimerl, S. Velsko, L. Davis, and F. Wang, “Progress in nonlinear optical materials for high power lasers,” Prog. Cryst. Growth Charact. Mater.20(1-2), 59–113 (1990).
[CrossRef]

D. Eimerl, L. Davis, S. Velsko, E. K. Graham, and A. Zalkin, “Optical, mechanical, and thermal properties of barium borate,” J. Appl. Phys.62(5), 1968 (1987).
[CrossRef]

Gösele, U.

U. Gösele and Q. Tong, “Semiconductor wafer bonding,” Annu. Rev. Mater. Sci.28(1), 215–241 (1998).
[CrossRef]

Gottschall, T.

Graham, E. K.

D. Eimerl, L. Davis, S. Velsko, E. K. Graham, and A. Zalkin, “Optical, mechanical, and thermal properties of barium borate,” J. Appl. Phys.62(5), 1968 (1987).
[CrossRef]

Gronloh, B.

R. Riedel, J. Rothhardt, K. Beil, B. Gronloh, A. Klenke, H. Höppner, M. Schulz, U. Teubner, C. Kränkel, J. Limpert, A. Tünnermann, M. J. Prandolini, and F. Tavella, “Thermal properties of borate crystals for high power optical parametric chirped-pulse amplification,” Opt. Express (submitted to).

Guy, A.

L. Bromley, A. Guy, and D. Hanna, “Synchronously pumped optical parametric oscillation in beta-barium borate,” Opt. Commun.67(4), 3–7 (1988).
[CrossRef]

Hädrich, S.

Hanna, D.

L. Bromley, A. Guy, and D. Hanna, “Synchronously pumped optical parametric oscillation in beta-barium borate,” Opt. Commun.67(4), 3–7 (1988).
[CrossRef]

Höppner, H.

R. Riedel, J. Rothhardt, K. Beil, B. Gronloh, A. Klenke, H. Höppner, M. Schulz, U. Teubner, C. Kränkel, J. Limpert, A. Tünnermann, M. J. Prandolini, and F. Tavella, “Thermal properties of borate crystals for high power optical parametric chirped-pulse amplification,” Opt. Express (submitted to).

Huang, Y. C.

Iwasa, M.

M. Iwasa, T. Ueno, and R. C. Bradt, “Fracture Toughness of Quartz and Sapphire Single Crystals at Room Temperature,” Zairyo30(337), 1001–1004 (1981).
[CrossRef]

Jansen, F.

Jauregui, C.

Kienel, M.

Klenke, A.

A. Klenke, S. Breitkopf, M. Kienel, T. Gottschall, T. Eidam, S. Hädrich, J. Rothhardt, J. Limpert, and A. Tünnermann, “530 W, 1.3 mJ, four-channel coherently combined femtosecond fiber chirped-pulse amplification system,” Opt. Lett.38(13), 2283–2285 (2013).
[CrossRef] [PubMed]

R. Riedel, J. Rothhardt, K. Beil, B. Gronloh, A. Klenke, H. Höppner, M. Schulz, U. Teubner, C. Kränkel, J. Limpert, A. Tünnermann, M. J. Prandolini, and F. Tavella, “Thermal properties of borate crystals for high power optical parametric chirped-pulse amplification,” Opt. Express (submitted to).

Kränkel, C.

R. Riedel, J. Rothhardt, K. Beil, B. Gronloh, A. Klenke, H. Höppner, M. Schulz, U. Teubner, C. Kränkel, J. Limpert, A. Tünnermann, M. J. Prandolini, and F. Tavella, “Thermal properties of borate crystals for high power optical parametric chirped-pulse amplification,” Opt. Express (submitted to).

Liem, A.

Limpert, J.

Lin, S. T.

Lin, Y. Y.

Maiman, T.

T. Maiman, “Stimulated optical radiation in ruby,” Nature187(4736), 493–494 (1960).
[CrossRef]

Nikogosyan, D. N.

D. N. Nikogosyan, “Beta Barium Borate (BBO): a review of its properties and applications,” Appl. Phys. A368, 359-368 (1991).

Otto, H.

Peschel, T.

Piskarskas, A. P.

A. Dubietis, R. Butkus, and A. P. Piskarskas, “Trends in chirped pulse optical parametric amplification,” IEEE J. Sel. Top. Quantum Electron.12(2), 163–172 (2006).
[CrossRef]

Prandolini, M. J.

R. Riedel, J. Rothhardt, K. Beil, B. Gronloh, A. Klenke, H. Höppner, M. Schulz, U. Teubner, C. Kränkel, J. Limpert, A. Tünnermann, M. J. Prandolini, and F. Tavella, “Thermal properties of borate crystals for high power optical parametric chirped-pulse amplification,” Opt. Express (submitted to).

Riedel, R.

R. Riedel, J. Rothhardt, K. Beil, B. Gronloh, A. Klenke, H. Höppner, M. Schulz, U. Teubner, C. Kränkel, J. Limpert, A. Tünnermann, M. J. Prandolini, and F. Tavella, “Thermal properties of borate crystals for high power optical parametric chirped-pulse amplification,” Opt. Express (submitted to).

Rothhardt, J.

Schulz, M.

R. Riedel, J. Rothhardt, K. Beil, B. Gronloh, A. Klenke, H. Höppner, M. Schulz, U. Teubner, C. Kränkel, J. Limpert, A. Tünnermann, M. J. Prandolini, and F. Tavella, “Thermal properties of borate crystals for high power optical parametric chirped-pulse amplification,” Opt. Express (submitted to).

Shy, J. T.

Stutzki, F.

Tavella, F.

R. Riedel, J. Rothhardt, K. Beil, B. Gronloh, A. Klenke, H. Höppner, M. Schulz, U. Teubner, C. Kränkel, J. Limpert, A. Tünnermann, M. J. Prandolini, and F. Tavella, “Thermal properties of borate crystals for high power optical parametric chirped-pulse amplification,” Opt. Express (submitted to).

Teubner, U.

R. Riedel, J. Rothhardt, K. Beil, B. Gronloh, A. Klenke, H. Höppner, M. Schulz, U. Teubner, C. Kränkel, J. Limpert, A. Tünnermann, M. J. Prandolini, and F. Tavella, “Thermal properties of borate crystals for high power optical parametric chirped-pulse amplification,” Opt. Express (submitted to).

Tong, Q.

U. Gösele and Q. Tong, “Semiconductor wafer bonding,” Annu. Rev. Mater. Sci.28(1), 215–241 (1998).
[CrossRef]

Tünnermann, A.

Ueno, T.

M. Iwasa, T. Ueno, and R. C. Bradt, “Fracture Toughness of Quartz and Sapphire Single Crystals at Room Temperature,” Zairyo30(337), 1001–1004 (1981).
[CrossRef]

Velsko, S.

D. Eimerl, S. Velsko, L. Davis, and F. Wang, “Progress in nonlinear optical materials for high power lasers,” Prog. Cryst. Growth Charact. Mater.20(1-2), 59–113 (1990).
[CrossRef]

D. Eimerl, L. Davis, S. Velsko, E. K. Graham, and A. Zalkin, “Optical, mechanical, and thermal properties of barium borate,” J. Appl. Phys.62(5), 1968 (1987).
[CrossRef]

Wang, F.

D. Eimerl, S. Velsko, L. Davis, and F. Wang, “Progress in nonlinear optical materials for high power lasers,” Prog. Cryst. Growth Charact. Mater.20(1-2), 59–113 (1990).
[CrossRef]

Zalkin, A.

D. Eimerl, L. Davis, S. Velsko, E. K. Graham, and A. Zalkin, “Optical, mechanical, and thermal properties of barium borate,” J. Appl. Phys.62(5), 1968 (1987).
[CrossRef]

Annu. Rev. Mater. Sci. (1)

U. Gösele and Q. Tong, “Semiconductor wafer bonding,” Annu. Rev. Mater. Sci.28(1), 215–241 (1998).
[CrossRef]

Appl. Phys. A (1)

D. N. Nikogosyan, “Beta Barium Borate (BBO): a review of its properties and applications,” Appl. Phys. A368, 359-368 (1991).

IEEE J. Sel. Top. Quantum Electron. (1)

A. Dubietis, R. Butkus, and A. P. Piskarskas, “Trends in chirped pulse optical parametric amplification,” IEEE J. Sel. Top. Quantum Electron.12(2), 163–172 (2006).
[CrossRef]

J. Appl. Phys. (1)

D. Eimerl, L. Davis, S. Velsko, E. K. Graham, and A. Zalkin, “Optical, mechanical, and thermal properties of barium borate,” J. Appl. Phys.62(5), 1968 (1987).
[CrossRef]

Nature (1)

T. Maiman, “Stimulated optical radiation in ruby,” Nature187(4736), 493–494 (1960).
[CrossRef]

Opt. Commun. (1)

L. Bromley, A. Guy, and D. Hanna, “Synchronously pumped optical parametric oscillation in beta-barium borate,” Opt. Commun.67(4), 3–7 (1988).
[CrossRef]

Opt. Express (2)

Opt. Lett. (3)

Prog. Cryst. Growth Charact. Mater. (1)

D. Eimerl, S. Velsko, L. Davis, and F. Wang, “Progress in nonlinear optical materials for high power lasers,” Prog. Cryst. Growth Charact. Mater.20(1-2), 59–113 (1990).
[CrossRef]

Rev. Sci. Instrum. (1)

G. Cerullo and S. De Silvestri, “Ultrafast optical parametric amplifiers,” Rev. Sci. Instrum.74(1), 1 (2003).
[CrossRef]

Zairyo (1)

M. Iwasa, T. Ueno, and R. C. Bradt, “Fracture Toughness of Quartz and Sapphire Single Crystals at Room Temperature,” Zairyo30(337), 1001–1004 (1981).
[CrossRef]

Other (11)

G. Kalkowski, S. Risse, C. Rothhardt, M. Rohde, and R. Eberhardt, “Optical contacting of low-expansion materials,” in Optical Manufacturing and Testing IX, J. H. Burge, O. W. Fähnle, and R. Williamson, eds. (SPIE, 2011), Vol. 8126, pp. 1–7.

M. Bass, C. DeCusatis, J. Enoch, V. Lakshminarayanan, G. Li, C. MacDonald, V. Mahajan, and E. Van Stryland, Handbook of Optics, Third Edition Volume IV: Optical Properties of Materials, Nonlinear Optics, Quantum Optics (set), Handbook of Optics (McGraw-Hill Education, 2009).

Z. Rappoport, CRC Handbook of Tables for Organic Compound Identification (CRC Press, 1985).

C. Rothhardt, M. Rekas, G. Kalkowski, N. Haarlammert, R. Eberhardt, and A. Tünnermann, “Fabrication of a high power Faraday isolator by direct bonding,” in Proc. SPIE 8601, Fiber Lasers X: Technology, Systems, and Applications, S. T. Hendow, ed. (2013), Vol. 8601, p. 86010T–86010T–7.

A. Smith, “SNLO,” http://www.as-photonics.com/snlo .

A. E. Siegman, Lasers (University Science Books, 1986).

D. N. Nikogosyan, Properties of Optical and Laser-Related Materials: A Handbook (Wiley, 1997).

Kyocera Headquarters, Single Crystal Sapphire (2010), pp. 1–8.

R. Riedel, J. Rothhardt, K. Beil, B. Gronloh, A. Klenke, H. Höppner, M. Schulz, U. Teubner, C. Kränkel, J. Limpert, A. Tünnermann, M. J. Prandolini, and F. Tavella, “Thermal properties of borate crystals for high power optical parametric chirped-pulse amplification,” Opt. Express (submitted to).

S. Kaplan and L. Hanssen, “Normal infrared spectral emittance of Al203,” in Optical Diagnostic Methods for Inorganic Transmissive Materials (SPIE, 1998), Vol. 3425, pp. 120–125.

P. Baum, D. Charalambidis, J. A. Fülöp, U. Kleineberg, F. Krausz, G. Szabó, G. Tsakiris, K. Varjú, L. Veisz, and M. Vrakking, “The Attosecond Light Pulse Source (ALPS) of the Extreme Light Infrastructure (ELI),” http://www.eli-hu.hu/uploads/File/Ceges_doksik_2013/Science/ELI_ALPS_Science_and_Technology.pdf .

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Figures (13)

Fig. 1
Fig. 1

Temperature difference in BBO single crystal (a) and BBO-sapphire sandwich (b), the black arrow indicates the incident beam.

Fig. 2
Fig. 2

Main stresses in BBO single crystal (a) and BBO-sapphire sandwich (b), the black arrow indicates the incident beam.

Fig. 3
Fig. 3

AFM measurements of the uncoated BBO surfaces.

Fig. 4
Fig. 4

AFM measurements of the protection coated BBO surfaces.

Fig. 5
Fig. 5

AFM measurements of the sapphire samples.

Fig. 6
Fig. 6

Interferometric images of the BBO surface (image sizes: 10.1 x 7.9 mm2; (a): front; (b): back).

Fig. 7
Fig. 7

Interferometric images of the sapphire surface (image sizes: 9.6 x 7.9 mm2; (a): front; (b): back).

Fig. 8
Fig. 8

AFM measurement image of BBO substrate as delivered (a), after wiping with acetone (b) and after cleaning with mixture of ether and ethanol (c).

Fig. 9
Fig. 9

Photograph of the bonded stack, consisting of a BBO disk (10x10x2 mm3; θ = 22°; φ = 90°) between two sapphire disks (10x10x2 mm3 on bonded to the top side of the BBO crystal and 10x10x1 mm3 on bonded on the bottom side of the BBO crystal)

Fig. 10
Fig. 10

Beam profiles after passing the single crystal BBO (left images) or the sapphire BBO stack (right images) at different power; (a) and (b): P = 37 W; (c) and (d): P = 253 W.

Fig. 11
Fig. 11

Beam profile sections (left images: vertical cross-section, right images: horizontal cross-sections); (a) and (b) at P = 37 W and (c) and (d) at P = 253 W.

Fig. 12
Fig. 12

Surface temperature difference of the BBO single crystal and the bonded stack at different incident powers; (a) P = 37 W, (b) P = 253 W. At a power of 253 W the results of the simulation are inserted into the graph as a continuous line.

Fig. 13
Fig. 13

Maximum surface temperature of the single crystal and the bonded stack.

Tables (4)

Tables Icon

Table 1 Rms roughness revealed by AFM measurement of coated and uncoated BBO samples

Tables Icon

Table 2 Peak-to-valley surface flatness values (average of three samples of one production lot)

Tables Icon

Table 3 Surface roughness values before and after different cleaning procedures

Tables Icon

Table 4 Conversion efficiency at different input powers

Metrics