Tunable partial polarization beam splitter and optomechanically induced Faraday effect

Abstract

The polarization beam splitter (PBS) is a crucial photonic element to separately extract transverse-electric and transverse-magnetic polarizations from propagating light fields. Here, we propose a concise, continuously tunable, and all-optical partial PBS in a vector optomechanical system which contains two orthogonal polarized cavity modes with degenerate frequency. The results show that one can manipulate the polarization states of different output fields by tuning the polarization angle of the pumping field and the system functions as a partial PBS when the pump laser polarizes vertically or horizontally. As a significant application of the tunable PBS, we propose a scheme of implementing quantum walks in resonator arrays without the aid of other auxiliary systems. Furthermore, we investigate the optomechanically induced Faraday effect in a vector optomechanical system which enables arbitrary tailoring of the input lights and the behaviors of polarization angles of the output fields in the undercoupling, critical coupling, and overcoupling regimes. Our findings prove the optomechanical system is a potential platform to manipulate the polarization states in multimode resonators and boost the process of applications related to polarization modulation.