Feedback Control of Two-mode Output Entanglement and Steering in Cavity Optomechanics

TL;DR

This paper demonstrates that feedback control in a two-mode cavity optomechanical system enhances output entanglement and steering, enabling secure quantum teleportation and two-way steering even with losses.

Contribution

It introduces a feedback scheme that improves entanglement and steering in cavity optomechanics, surpassing previous limitations without feedback.

Findings

Achieves fidelity > 2/3 for secure teleportation

Enables two-way steering between output modes with loss

Demonstrates control of entanglement via feedback

Abstract

We show that the closed-loop control obtained by feeding back the derivative of the signal from the homodyne measurement of one mode of the light exiting a two-mode optical cavity interacting with a mechanical resonator permits to control and increase optical output entanglement. In particular, the proposed feedback-enhanced setup allows to achieve a fidelity of coherent state teleportation greater than the threshold value of 2/3 for secure teleportation, and two-way steering between the two cavity's output modes down the line in presence of loss, which otherwise would not be possible without feedback