Macroscopic quantum entanglement in modulated optomechanics

TL;DR

This paper proposes a method to generate strong, steady-state quantum entanglement between mechanical oscillators in a modulated optomechanical system, enabling applications like high-fidelity teleportation and robustness against thermal noise.

Contribution

It introduces a novel approach combining cavity cooling and parametric interaction to surpass previous entanglement bounds in optomechanical systems.

Findings

Achieves high-purity entanglement from thermal states

Enables high-fidelity continuous-variable teleportation

Demonstrates robustness against thermal fluctuations

Abstract

Quantum entanglement in mechanical systems is not only a key signature of macroscopic quantum effects, but has wide applications in quantum technologies. Here we proposed an effective approach for creating strong steady-state entanglement between two directly coupled mechanical oscillators (or a mechanical oscillator and a microwave resonator) in a modulated optomechanical system. The entanglement is achieved by combining the processes of a cavity cooling and the two-mode parametric interaction, which can surpass the bound on the maximal stationary entanglement from the two-mode parametric interaction. In principle, our proposal allows one to cool the system from an initial thermal state to an entangled state with high purity by a monochromatic driving laser. Also, the obtained entangled state can be used to implement the continuous-variable teleportation with high fidelity. Moreover, our proposal is robust against the thermal fluctuations of the mechanical modes under the condition of strong optical pumping.