Enhancement of mechanical squeezing via feedback control

TL;DR

This paper demonstrates how feedback control can significantly improve mechanical squeezing and mitigate background noise, advancing the preparation of nonclassical mechanical states at room temperature.

Contribution

It introduces feedback-induced spring softening and hardening techniques to enhance position and momentum squeezing in mechanical systems.

Findings

Feedback-induced spring softening enhances position squeezing.

Spring hardening enables momentum squeezing with pure position measurement.

Feedback reduces degradation from background mechanical modes.

Abstract

We explore the generation of nonclassical mechanical states by combining continuous position measurement and feedback control. We find that feedback-induced spring softening can greatly enhance position squeezing. Conversely, even with a pure position measurement, we find that spring hardening can enable momentum squeezing. Beyond enhanced squeezing, we show that feedback also mitigates degradation introduced by background mechanical modes. Together, this significantly lowers the barrier to measurement-based preparation of nonclassical mechanical states at room temperature.