Generation and detection of squeezed light on a single silicon photonic chip

Abstract

The ability to generate and detect quantum states of light on a single integrated photonic device is essential to scale quantum photonics into useful quantum technologies. Integrating the required capabilities into complementary-metal-oxide-semiconductor compatible monolithic chips can reduce cost and unlock new functionality through miniaturisation. In this work we demonstrate a single silicon-on-insulator photonic integrated circuit for the monolithic generation and detection of quantum light on a commercially available platform that operates entirely at room temperature. Specifically, we leverage spontaneous four-wave mixing in silicon waveguides to produce squeezed light which is subsequently detected by photodiodes operating in a pulsed homodyne detector configuration on the same chip as the source. We directly measure $0.25(1)$ dB of squeezing, including contributions from waveguide propagation loss and detection inefficiency, and include a detailed analysis of the impact of nonlinear loss on the squeezing levels achievable using this platform.