A twin-crystal device consisting of a pair of two identically cut KTP crystals of length l = 6 mm mounted with their optical axes symmetrically crossed is used to circumvent conversion-efficiency limitations that are due to the aperture effect in type-II (oeo) critically phase-matched second-harmonic generation (SHG) at λ = 1.3 and λ = 2.532 μm. A single-pass increase of as great as 3.2–3.5 times the conversion efficiency of a single crystal is obtained with this angle-tuned device at these wavelengths. This enhancement results from an increased effective coherence length of the interaction compared with that of a single bulk crystal of length 2l. We show that cavity-enhanced critically phase-matched type-II SHG can be easily performed with the twin device, allowing for walk-off as well as phase compensation for the fundamental-resonating ordinary and extraordinary waves at λ = 1.30 μm. Potential implementations of this device in other single-cavity-enhanced parametric interactions, such as doubly resonant optical parametric oscillation and degenerate sum-or difference-frequency mixing, are discussed.
© 1994 Optical Society of AmericaFull Article | PDF Article
OSA Recommended Articles
Jean-Jacques Zondy, Dmitri Kolker, Christophe Bonnin, and Dominique Lupinski
J. Opt. Soc. Am. B 20(8) 1695-1707 (2003)
Yanqing Liu, Hongwei Qi, Qingming Lu, Fapeng Yu, Zhengping Wang, Xinguang Xu, and Xian Zhao
Opt. Express 23(3) 2163-2173 (2015)
Appl. Opt. 37(3) 555-560 (1998)