Enhanced optical squeezing from a degenerate parametric amplifier via time-delayed coherent feedback

TL;DR

This paper demonstrates that time-delayed coherent feedback can significantly enhance optical squeezing in a degenerate parametric amplifier, reducing the required pump power and broadening the operational parameters for improved quantum noise reduction.

Contribution

The study introduces a simple setup to analyze how time-delayed coherent feedback improves optical squeezing in a DPA, showing enhanced performance over traditional configurations.

Findings

Enhanced squeezing on resonance and in sidebands

Reduced pump power needed for significant squeezing

Connection between feedback, stability, and squeezing quality

Abstract

A particularly simple setup is introduced to study the influence of time-delayed coherent feedback on the optical squeezing properties of the degenerate parametric amplifier (DPA). The possibility for significantly enhanced squeezing is demonstrated both on resonance and in sidebands, at a reduced pump power compared to the case without feedback. We study a broad range of operating parameters and their influence on the characteristic squeezing of the system. A classical analysis of the system dynamics reveals the connection between the feedback-modified landscape of stability and enhanced squeezing.