Physical Review Research

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

Su Direkci, K. Winkler, Corentin Gut, Klemens Hammerer, Markus Aspelmeyer, Y. Chen

Published Feb 16, 2024• 11 citations

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. Published by the American Physical Society 2024

DOI: 10.1103/physrevresearch.6.013175

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