Squeezed cooling of mechanical motion beyond the resolved-sideband limit

¹ School of Physics and Information Technology, Shaanxi Normal University - Xi'an 710061, PRC
² Department of Physics and Astronomy, Shanghai Jiao Tong University - Shanghai 200240, PRC

^(a) zhanglincn@snnu.edu.cn

Received: 12 December 2017
Accepted: 30 April 2018

Abstract

Cavity optomechanics provides a unique platform for controlling micromechanical systems by means of optical fields that cross the classical-quantum boundary to achieve solid foundations for quantum technologies. Currently, optomechanical resonators have become promising candidates for the development of precisely controlled nano-motors, ultrasensitive sensors and robust quantum information processors. For all these applications, a crucial requirement is to cool the mechanical resonators down to their quantum ground states. In this paper, we present a novel cooling scheme to further cool a micromechanical resonator via the noise squeezing effect. One quadrature in such a resonator can be squeezed to induce enhanced fluctuations in the other, “heated” quadrature, which can then be used to cool the mechanical motion via conventional optomechanical coupling. Our theoretical analysis and numerical calculations demonstrate that this squeeze-and-cool mechanism offers a quick technique for deeply cooling a macroscopic mechanical resonator to an unprecedented temperature region below the zero-point fluctuations.