Fano resonances and their control in optomechanics

TL;DR

This paper explores Fano resonances in cavity optomechanics, demonstrating their controllability via coupling fields and cavity configurations, and analyzing their sensitivity to decay parameters.

Contribution

It introduces the existence and control of Fano resonances in optomechanical systems, including their splitting and tuning using double cavities and a single optomechanical mirror.

Findings

Fano resonances occur in cavity optomechanics due to interfering fields.

The width of the Fano resonance can be controlled by the coupling field.

Double cavities enable splitting and tuning of Fano resonances.

Abstract

The Fano line profiles, originally discovered in the context of photoionization, have been found to occur in a large class of systems like resonators, metamaterials, plasmonics. We demonstrate the existence of such resonances in cavity optomechanics by identifying the interfering contributions to the fields generated at antiStokes and Stokes frequencies. Unlike the atomic systems, the optomechanical systems provide great flexibility as the width of the resonance is controlled by the coupling field. We further show how the double cavities coupled by a single optomechanical mirror can lead to the splitting of the Fano resonance and how the second cavity can be used to tune the Fano resonances. The Fano resonances are quite sensitive to the decay parameters associated with cavities and the mechanical mirror. Such resonances can be studied by both pump probe experiments as well as via the spectrum of the quantum fluctuations in the output fields.