Thermal inhibition of high-power second-harmonic generation in periodically poled LiNbO3 and LiTaO3 crystals

A coupled thermo-optical model shows strong thermal inhibition of second-harmonic generation (SHG) in periodically poled (PP) LiNbO3 (PPLN) and stoichiometric LiTaO3 (PPSLT) crystals. Three-dimensional simulations performed for a 1.064μm fundamental wavelength pulsed nanosecond laser beam 150μm in radius show the onset of significant temperature nonuniformities along and across the irradiated zone, and strong thermal dephasing and inhibition of SHG in these crystals for input powers >10W. PPSLT is found to have a significant advantage over PPLN due to the higher heat conductance, decreasing these temperature nonuniformities and allowing one to maintain the irradiated zone within the corresponding SHG temperature tolerance range (ΔT≈3K).

[1]  S. V. Chernikov,et al.  6-W Average power green light generation using seeded high power ytterbium fibre amplifier and periodically poled KTP , 2000 .

[2]  N. Bloembergen,et al.  Interactions between light waves in a nonlinear dielectric , 1962 .

[3]  D. Hanna,et al.  Highly efficient green-light generation by quasi-phase-matched frequency doubling of picosecond pulses from an amplified mode-locked Nd:YLF laser. , 1996, Optics letters.

[4]  David Eger,et al.  Temperature-dependent Sellmeier equation for the refractive index of stoichiometric lithium tantalate. , 2003, Optics letters.

[5]  Nan Ei Yu,et al.  Stable High-Power Green Light Generation with Thermally Conductive Periodically Poled Stoichiometric Lithium Tantalate , 2004 .

[6]  Martin M. Fejer,et al.  UV and visible absorption in LiTaO3 , 1999, Photonics West.

[7]  R L Byer,et al.  42%-efficient single-pass cw second-harmonic generation in periodically poled lithium niobate. , 1997, Optics letters.

[8]  E. O. Schulz-Dubois,et al.  Laser Handbook , 1972 .

[9]  H Karlsson,et al.  Efficient Nd:YAG Laser Frequency Doubling with Periodically Poled KTP. , 1998, Applied optics.

[10]  Jay W. Dawson,et al.  Thermally induced dephasing in periodically poled KTP frequency-doubling crystals , 2004 .

[11]  Takunori Taira,et al.  High-Power Continuous Wave Green Generation by Single-Pass Frequency Doubling of a Nd:GdVO4 Laser in a Periodically Poled MgO:LiNbO3 Operating at Room Temperature , 2003 .

[12]  M. Fejer,et al.  Periodically poled LiNbO3 for high‐efficiency second‐harmonic generation , 1991 .

[13]  M M Fejer,et al.  Vapor-transport equilibrated near-stoichiometric lithium tantalate for frequency-conversion applications. , 2004, Optics letters.

[14]  M. Fejer,et al.  Green-induced infrared absorption in MgO doped LiNbO3 , 2001 .

[15]  G. Rosenman,et al.  Highly efficient doubling of a high-repetition-rate diode-pumped laser with bulk periodically poled KTP. , 1997, Optics letters.