Suspended AlGaAs-Integrated Nonlinear Photonics

AlGaAs is a promising integrated nonlinear photonics material with enormous optical nonlinearity and high refractive index. Nevertheless, presently AlGaAs microring resonators exhibiting high quality factors and tight optical confinement rely predominantly on wafer bonding techniques, which entail an intricate fabrication process. Here, we present suspended AlGaAs waveguides and resonators as a viable platform for high efficiency integrated nonlinear photonics. The suspended microring resonator formed by combined plasma dry etching and chemical wet etching exhibits an intrinsic quality factor Q of 2.1*106, and Kerr comb generation with milliwatt level threshold is recorded. Our demonstration opens up a new prospect for employing AlGaAs devices in integrated nonlinear photonics.