The critical Kerr non-linear optical cavity in the presence of internal loss and driving noise

TL;DR

This paper provides a detailed theoretical analysis of Kerr non-linear cavities, demonstrating that significant quantum noise reduction is possible despite optical loss and classical noise, with the main limitation being optical loss.

Contribution

It introduces a rigorous time-domain model for Kerr non-linear cavities accounting for realistic experimental conditions, including loss and classical noise, and predicts achievable squeezing levels.

Findings

Squeezing levels are limited by optical loss, not driving noise.

Proper operating point selection enables amplitude quadrature squeezing.

Model aligns well with experimental noise spectra.

Abstract

We theoretically analyze the noise transformation of a high power continuouswave light field that is reflected off a critical Kerr non-linear cavity (KNLC). Our investigations are based on a rigorous treatment in the time-domain. Thereby, realistic conditions of a specific experimental environment including optical intra-cavity loss and strong classical driving noise can be modeled for any KNLC. We show that even in the presence of optical loss and driving noise considerable squeezing levels can be achieved. We find that the achievable squeezing levels are not limited by the driving noise but solely by the amount of optical loss. Amplitude quadrature squeezing of the reflected mean field is obtained if the KNLC's operating point is chosen properly. Consistently, a KNLC can provide a passive, purely optical reduction of laser power noise as experimentally demonstrated in [1]. We apply our model to this experiment and find good agreement with measured noise spectra.