Strong Mechanical Squeezing and its Detection

TL;DR

This paper demonstrates an efficient method to generate and detect significant mechanical squeezing in an optomechanical system using a parametric amplifier, with analytical insights and potential for enhanced squeezing via feedback.

Contribution

It introduces a novel mechanism employing a parametric amplifier inside the cavity to transfer quantum squeezing from photons to phonons with high efficiency, and provides analytical relations for system parameters.

Findings

Achieved 50% mechanical squeezing limited by the parametric amplifier

Analytical dependence of squeezing on system parameters like gain and temperature

Cavity output squeezing correlates directly with mirror squeezing, enabling measurement

Abstract

We report an efficient mechanism to generate a squeezed state of a mechanical mirror in an optomechanical system. We use especially tuned parametric amplifier (PA) inside the cavity and the parametric photon phonon processes to transfer quantum squeezing from photons to phonons with almost 100\% efficiency. We get 50\% squeezing of the mechanical mirror which is limited by the PA. We present analytical results for the mechanical squeezing thus enabling one to understand the dependence of squeezing on system parameters like gain of PA, cooperativity, temperature. As in cooling experiments the detrimental effects of mirror's Brownian and zero point noises are strongly suppressed by the pumping power. By judicious choice of the phases, the cavity output is squeezed only if the mirror is squeezed thus providing us a direct measure of the mirror's squeezing. Further considerable larger squeezing of the mirror can be obtained by adding the known feedback techniques.