Continuous-Wave Second-Harmonic Generation in Orientation-Patterned Gallium Phosphide Waveguides at Telecom Wavelengths

A new process to produce orientation-patterned gallium phosphide (OP-GaP) on GaAs with almost perfectly parallel domain boundaries is presented. Taking advantage of the chemical selectivity between phosphides and arsenides, OP-GaP processed into suspended shallow-ridge waveguides. Efficient second-harmonic generation from telecom wavelengths achieved in both Type-I Type-II polarisation configurations. The highest observed conversion efficiency 200% W–1 cm–2, a bandwidth 2.67 nm 1 mm-long waveguide. variation wavelength closely follows squared cardinal sine function, excellent agreement theory, confirming good uniformity poling period over entire length