Nonreciprocal Photon Transport in a Chiral Optomechanical System

Chiral interaction between light and quantum emitters leads to emergence development of chiral quantum optics and stimulates a wide range of practical applications in quantum regime, such as single-photon isolation and photon unidirectional emission. Cavity optomechanics studying the interaction between optical and mechanical resonators plays an important role in the field of quantum optics. However, how to achieve the chiral interaction between light and mechanical oscillators and explore the applications of the chiral optomechanical systems are still difficult encountered in cavity optomechanics. Here, a method is proposed to achieve chiral optomechanical interaction by exploiting directional squeezed light in a multimode optomechanical system. Based on the chiral interaction between photon and phonon, the nonreciprocal photon transport at a single-photon level can be realized. An isolation ratio of $>40\text{dB}$ and a negligible insertion loss for the photonic isolator are obtained. This method paves the way to realize chiral optomechanical interaction for conducting chiral optomechanics and opens up the prospect of exploring and utilizing chiral photon–phonon manipulation in the quantum regime.