Non-classical correlations in a two-mode optomechanical system

TL;DR

This paper investigates quantum correlations in a tripartite optomechanical system, demonstrating the transfer and resilience of entanglement and discord among optical and mechanical modes under various conditions.

Contribution

It provides a detailed analysis of quantum correlations, including entanglement and discord, in a tripartite optomechanical system, highlighting conditions for their simultaneous presence and robustness.

Findings

Simultaneous bipartite entanglements can be achieved via quantum correlation transfer.

Quantum correlations exist even without squeezed light across wide parameters.

Optical modes show stronger correlations and greater resilience to environmental effects.

Abstract

The pairwise quantum correlations in a tripartite optomechanical system comprising a mechanical mode and two optical modes are analyzed. The Simon criterion is used as a witness of the separability. Whereas, the Gaussian discord is employed to capture the quantumness of correlations. Both entanglement and Gaussian discord are evaluated as functions of the parameters characterizing the environment and the system (temperature, squeezing and optomechanical coupling). We work in the resolved-sideband regime. We show that it is possible to reach simultaneous three bipartite entanglements via the quantum correlations transfer from the squeezed light to the system. While, even without squeezed light, the quantumness of correlations can be captured simultaneously between the three modes for a very wide range of parameters. Specifically, we find that the two optical modes exhibit more quantum correlations in comparison with the entangled mechanical-optical modes. Finally, unlike the two hybrid subsystems, the purely optical one seems more resilient against the environmental destructive effects.