Nonreciprocal conversion between microwave and optical photons in electro-optomechanical systems

TL;DR

This paper proposes a method for nonreciprocal microwave-optical photon conversion in an electro-optomechanical system, exploiting broken time-reversal symmetry and quantum interference to enable directional photon transfer and potential applications like circulators.

Contribution

It introduces a novel electro-optomechanical scheme for nonreciprocal photon conversion and circulator functionality using two mechanical modes and quantum interference effects.

Findings

Nonreciprocal conversion occurs at two frequencies with opposite directions.

The system enhances conversion in one direction while suppressing it in the reverse.

Potential for implementing nonreciprocal devices between different frequency modes.

Abstract

We propose to demonstrate nonreciprocal conversion between microwave and optical photons in an electro-optomechanical system where a microwave mode and an optical mode are coupled indirectly via two non-degenerate mechanical modes. The nonreciprocal conversion is obtained in the broken time-reversal symmetry regime, where the conversion of photons from one frequency to the other is enhanced for constructive quantum interference while the conversion in the reversal direction is suppressed due to destructive quantum interference. It is interesting that the nonreciprocal response between the microwave and optical modes in the electro-optomechanical system appears at two different frequencies with opposite directions. The proposal can be used to realize nonreciprocal conversion between photons of any two distinctive modes with different frequencies. Moreover, the electro-optomechanical system can also be used to construct a three-port circulator for three optical modes with distinctively different frequencies by adding an auxiliary optical mode coupled to one of the mechanical modes.