Multicolor quadripartite entanglement from an optomechanical cavity

Abstract

We investigate the generation of multicolor quadripartite entangled beams of light with continuous variables via optomechanical coupling in an optical cavity. It is found that the genuine quadripartite entanglement can be achieved among the Stokes and anti-Stokes sidebands of two driven cavity fields. This entanglement still exists for the environment temperature up to about $50\phantom{\rule{4pt}{0ex}}\text{K}$. We also show that the obtained genuine quadripartite entanglement actually results from concurrent four-wave-mixing processes in the system, which can, in principle, be generalized to obtain a genuine $2N$-partite entangled state of light from a generic $N$-mode cavity optomechanical system.