Gallium phosphide transfer printing for integrated nonlinear photonics

Integrated nonlinear photonics has drawn an increased interest as it provides scalable, compact, and low cost solutions for a large range of applications. Indeed, the high confinement of the light in integrated waveguides allows for enhanced nonlinear effects. However, mature highly nonlinear platforms such as silicon-on-insulator (SOI) circuits suffer from nonlinear losses at telecom wavelengths caused by two-photon absorption. Moreover, the platform lacks a second order nonlinear susceptibility, which is not the case for wide bandgap III-V semiconductors. Recently, gallium phosphide-on-insulator (GaP-OI) has been proposed as an efficient platform for second and third order nonlinear applications [1] and last year we demonstrated as a proof of concept the transfer printing of GaP as a versatile technique for GaP hetero-integration [2] .