Squeezed light detection with an integrated coherent optical receiver

In recent years, silicon photonics has enabled unprecedented scaling of quantum optical systems and cost-effective integration of electronics for the generation, processing, and readout of quantum light. Quantum optoelectronic processing and readout are especially advantageous with silicon photonics via on-chip coherent optical receivers, which amplify the signal to achieve quantum-limited sensitivities and extract signal quadrature information with high bandwidths. In this work, we develop and realize a silicon photonic integrated coherent receiver with a small form factor, low knee power, and high shot-noise clearance. With the realized on-chip receiver, we detect squeezed vacuum and implement deterministic phase control for quantum state tomography. Furthermore, we devise a noise model and outline a design guide to aid the development of quantum-limited coherent optical receivers for both classical and quantum technologies. Our work paves the way for large-scale integration of these receivers for practical applications in quantum-enhanced optical communications, metrology, and photonic quantum computing.