Entanglement and Output Squeezing of Distant Optomechanical Systems Generated by Four-Level Atoms

A scheme is presented to generate entanglement of optical andmechanical modes in coupled cavity optomechanical system with two four-level atoms. Two distant movable mirrors and two cavity modes as well as mirror and the adjacent or the distant cavity mode are all entangled, and the entanglement curve of two movable mirrors is a symmetrical distribution when ∆ is equal to ωm. Furthermore, we also investigate the output entanglement of two cavity fields, and find the squeezing spectrum is affected by the mirror frequency and the Rabi frequency of laser field.