Noise modelling of waveguide based squeezed light sources

TL;DR

This paper analyzes waveguide-based squeezed-light sources, focusing on loss mechanisms and phase noise, and proposes a cascaded architecture to enhance quantum noise reduction for applications like gravitational wave detection.

Contribution

It provides a detailed analysis of waveguide squeezers, explores loss mitigation strategies, and introduces a cascaded design to improve squeezing performance.

Findings

Waveguide-based sources show promise due to their robustness and low phase noise.

Cascaded squeezer architecture can mitigate losses and improve squeezing.

Waveguide sources are suitable for integration in advanced gravitational wave detectors.

Abstract

Squeezed states of light are used for precision metrology and quantum-enhanced measurements, with applications spanning communication and sensing. State-of-the-art squeezed-light sources typically rely on optical cavities to achieve high, usable levels of squeezing. Recently, waveguide-based squeezed-light sources have demonstrated significant improvements in achievable squeezing, with performance currently limited by fabrication-induced losses. In this work, we present a detailed analysis of waveguide-based squeezers, examining the effects of phase noise, multiple loss mechanisms, and fundamental light leakage seeding the squeezer. We further investigate a cascaded squeezer architecture, in which a second waveguide operates as a phase-sensitive amplifier to mitigate out-coupling and detection losses. Owing to their ease of integration, robustness to high pump powers, and low intrinsic phase noise, we propose waveguide-based squeezed-light sources as a promising alternative for quantum noise reduction in future gravitational wave detectors, such as the Einstein Telescope.