Fabrication of a Highly Efficient Quasi-phase-match Device for Blue-Violet Second-Harmonic Generation.

Abstract

We present a method for controlling the shape of the domain-inverted structure in an off-cut MgO: LiNbO3 crystal utilizing two-dimensional high-voltage application. Using this technique, a periodically domain-inverted structure with a period of 3.2 Jim and thickness of 2.0 μm was fabricated over a 10-mminteraction length. This structure has made possible sufficient overlaps between propagation modes and domain inversion in the waveguide. Using this structure, we demonstrated a cw blue-violet second-harmonic generation of 17.3 mW at the wavelength of 426 nm with a single pass of 55 mW of cw AlGaAs laser diode input, which corresponded to a 31 % power conversion efficiency.