Phonon antibunching effect in coupled nonlinear micro/nanomechanical resonator at finite temperature

TL;DR

This paper explores how phonon antibunching in coupled nonlinear MEMS/NEMS resonators is affected by temperature, revealing conditions for optimal antibunching and how thermal noise influences phonon correlations.

Contribution

It provides a detailed analysis of phonon antibunching at finite temperatures, including optimal conditions and the impact of thermal noise, which was not thoroughly studied before.

Findings

Phonon antibunching occurs at low temperature with weak nonlinearity and coupling.

Thermal noise can degrade or destroy antibunching effects.

Strong driving can help preserve phonon correlations against thermal noise.

Abstract

In this study, we investigate the phonon antibunching effect in a coupled nonlinear micro/nanoelectromechanical system (MEMS/NEMS) resonator at a finite temperature. In the weak driving limit, the optimal condition for phonon antibunching is given by solving the stationary Liouville-von Neumann master equation. We show that at low temperature, the phonon antibunching effect occurs in the regime of weak nonlinearity and mechanical coupling, which is confirmed by analytical and numerical solutions. We also find that thermal noise can degrade or even destroy the antibunching effect for different mechanical coupling strengths. Furthermore, a transition from strong antibunching to bunching for phonon correlation has been observed in the temperature domain. Finally, we find that a suitably strong driving in the finite-temperature case would help to preserve an optimal phonon correlation against thermal noise.