摘要
We investigate the quantum entanglement in a double-cavity optomechanical system consisting of an optomechanical cavity and an auxiliary cavity,where the optomechanical cavity mode couples with the mechanical mode via radiation-pressure interaction,and simultaneously couples with the auxiliary cavity mode via nonreciprocal coupling.We study the entanglement between the mechanical oscillator and the cavity modes when the two cavities are reciprocally or non-reciprocally coupled.The logarithmic negativity E_(n)^((1))(E_(n)^((2)))is adopted to describe the entanglement degree between the mechanical mode and the optomechanical cavity mode(the auxiliary cavity mode).We find that both E_(n)^((1))and E_(n)^((2))have maximum values in the case of reciprocal coupling.By using nonreciprocal coupling,E_(n)^((1))and E_(n)^((2))can exceed those maximum values,and a wider detuning region where the entanglement exists can be obtained.Moreover,the entanglement robustness with respect to the environment temperature is also effectively enhanced.
作者
刘元元
张智明
刘军浩
王金东
於亚飞
Yuan-Yuan Liu;Zhi-Ming Zhang;Jun-Hao Liu;Jin-Dong Wang;Ya-Fei Yu(Guangdong Provincial Key Laboratory of Nanophotonic Functional Materials and Devices(School of Information and Optoelectronic Science and Engineering),South China Normal University,Guangzhou 510006,China;Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials,South China Normal University,Guangzhou 510006,China)
基金
Project supported by the National Natural Science Foundation of China(Grant Nos.12047520,61941501,61775062,11574092,61378012,91121023,62071186 and 61771205).