Efficient Intermodal Four-Wave Mixing in AlGaAs-on-Insulator Waveguide

We demonstrate cross-polarized four-wave mixing with a conversion efficiency of -31.5 dB in a 2.5-mm-long AlGaAs-on-insulator waveguide with 80-mW pumping. We report the highest effective nonlinearity (278 W
^-1
m
⁻¹
) for intermodal four-wave mixing in integrated waveguides.