Spontaneous Parametric Down-Conversion in 4H-SiC Integrated Platform

Abstract

4H-silicon carbide (SiC) has recently emerged as a promising material for nonlinear photonic integrated circuits, thanks to its low loss, wide bandgap, as well as strong second-order ((Formula presented.)) and third-order ((Formula presented.)) nonlinearities. Though its unique crystal structure allows versatile (Formula presented.) processes, spontaneous parametric down-conversion (SPDC) still remains unrealized. In this work, photon-pair generation in a 4H-SiC-on-insulator integrated platform is demonstrated through modal-phase-matched type-I SPDC. Furthermore, type-0 and type-II (Formula presented.) nonlinear interactions are shown in 4H-SiC waveguides, thus highlighting the potential to exploit diverse phase-matching mechanisms on this platform. These results underscore the potential of 4H-SiC for advancing the development of integrated quantum photonics in the realms of quantum information processing and quantum communication.