Qubit assisted enhancement of quantum correlations in an optomechanical system

TL;DR

This paper theoretically demonstrates that coupling a qubit to an optomechanical system enhances quantum correlations like entanglement and discord, even at lower coupling strengths and higher temperatures, aiding quantum information tasks.

Contribution

It introduces a scheme where a qubit enhances quantum correlations in an optomechanical system, enabling lower coupling requirements and increased robustness against temperature effects.

Findings

Quantum correlations are significantly enhanced by mirror-qubit coupling.

Entanglement can be generated at lower optomechanical coupling strengths.

The scheme is robust against environmental temperature variations.

Abstract

We perform a theoretical study on quantum correlations in an optomechanical system where the mechanical mirror is perturbatively coupled to an auxiliary qubit. In our study, we consider logarithmic negativity to quantify the degree of stationary entanglement between the cavity field and mechanical mirror, and, Gaussian quantum discord as an witness of the quantumness of the correlation beyond entanglement. Utilizing experimentally feasible parameters, we show that both entanglement and quantum discord enhance significantly with increase in mirror-qubit coupling. Moreover, we find that in presence of the mirror-qubit coupling entanglement could be generated at a considerably lower optomechanical coupling strength, which is also extremely robust against the environmental temperature. Overall, our proposed scheme offers some considerable advantages for realizing the continuous-variable quantum information and communication.