Quasi-phase-matched (QPM) GaAs structures, 0.5 mm thick, 10 mm long, and with 61-μm grating periods, were grown by a combination of molecular-beam epitaxy and hydride vapor phase epitaxy. These were characterized by use of mid-IR second-harmonic generation (SHG) with a ZnGeP<sub>2</sub> (ZGP) optical parametric oscillator as a pump source. The SHG efficiencies of QPM GaAs and QPM LiNbO<sub>3</sub> were directly compared, and a ratio of nonlinear coefficients d<sub>14</sub>(GaAs)/d<sub>33</sub> (LiNbO<sub>3</sub>)=5.01±0.3 was found at 4.1-μm fundamental wavelength. For input pulse energies as low as 50μJ and ≈60-ns pulse duration, an internal SHG conversion efficiency of 33% was measured in QPM GaAs.
© 2002 Optical Society of America
(190.2620) Nonlinear optics : Harmonic generation and mixing
(190.4160) Nonlinear optics : Multiharmonic generation
(190.4360) Nonlinear optics : Nonlinear optics, devices
(190.4400) Nonlinear optics : Nonlinear optics, materials
(190.4720) Nonlinear optics : Optical nonlinearities of condensed matter
T. Skauli, K. L. Vodopyanov, T. J. Pinguet, A. Schober, O. Levi, L. A. Eyres, M. M. Fejer, J. S. Harris, B. Gerard, L. Becouarn, E. Lallier, and G. Arisholm, "Measurement of the nonlinear coefficient of orientation-patterned GaAs and demonstration of highly efficient second-harmonic generation," Opt. Lett. 27, 628-630 (2002)