Macroscopic quantum entanglement between an optomechanical cavity and a continuous field in presence of non-Markovian noise

TL;DR

This paper develops a framework to quantify macroscopic quantum entanglement in an optomechanical system influenced by non-Markovian noise, considering both cavity and continuous optical fields, with applications to gravitational-wave detectors.

Contribution

It introduces a novel numerical approach to measure entanglement in Gaussian optomechanical systems accounting for non-Markovian noise and both optical and cavity modes.

Findings

Entanglement persists under realistic noise conditions.

Applicable to gravitational-wave detectors like LIGO.

Provides parameter regimes for observing macroscopic entanglement.

Abstract

Probing quantum entanglement with macroscopic objects allows us to test quantum mechanics in new regimes. One way to realize such behavior is to couple a macroscopic mechanical oscillator to a continuous light field via radiation pressure. In view of this, the system that is discussed comprises an optomechanical cavity driven by a coherent optical field in the unresolved sideband regime where we assume Gaussian states and dynamics. We develop a framework to quantify the amount of entanglement in the system numerically. Different from previous work, we treat non-Markovian noise and take into account both the continuous optical field and the cavity mode. We apply our framework to the case of the Advanced Laser Interferometer Gravitational-Wave Observatory and discuss the parameter regimes where entanglement exists, even in the presence of quantum and classical noises.