# Optical unidirectional amplification in a three-mode optomechanical system

## TL;DR

This paper demonstrates optical unidirectional amplification in a three-mode optomechanical system, where interference effects enable the probe field to be amplified in one direction and suppressed in the opposite, promising for optical signal control.

## Contribution

The study introduces a novel three-mode optomechanical setup that achieves directional optical amplification through interference effects, expanding control over light transmission.

## Key findings

- Achieves unidirectional optical amplification and de-amplification.
- Demonstrates interference-based control of probe transmission.
- Provides a theoretical framework for optomechanical directional devices.

## Abstract

We study the directional amplification of an optical probe field in a three-mode optomechanical system, where the mechanical resonator interacts with two linearly-coupled optical cavities and the cavities are driven by strong optical pump fields. The optical probe field is injected into one of the cavity modes, and at the same time, the mechanical resonator is subject to a mechanical drive with the driving frequency equal to the frequency difference between the optical probe and pump fields. We show that the transmission of the probe field can be amplified in one direction and de-amplified in the opposite direction. This directional amplification or de-amplification results from the constructive or destruction interference between different transmission paths in this three-mode optomechanical system.