Dynamically creating tripartite resonance and dark modes in a multimode optomechanical system

TL;DR

This paper demonstrates a method to dynamically generate dark modes in a multimode optomechanical system using two pump tones, enabling control over resonance and mode properties for potential quantum information applications.

Contribution

It introduces a scheme to create dark modes with unmatched mechanical frequencies via double sideband pumping, expanding control in multimode optomechanical systems.

Findings

Dark modes can be dynamically created with unmatched mechanical frequencies.

Double sideband pumping enables on-resonance coupling and dark mode formation.

Breakdown of the rotating-wave approximation observed in certain configurations.

Abstract

We study a multimode optomechanical system where two mechanical oscillators are coupled to an electromagnetic cavity. Previously it has been shown that if the mechanical resonances have nearly equal frequencies, one can make the oscillators to interact via the cavity by strong pumping with a coherent pump tone. One can view the interaction also as emergence of an electromagnetically dark mode which gets asymptotically decoupled from the cavity and has a linewidth much smaller than that of the bare cavity. The narrow linewidth and long lifetime of the dark mode could be advantageous for example in information storage and processing. Here we investigate the possibility to create dark modes dynamically using two pump tones. We show that if the mechanical frequencies are intrinsically different, one can bring the mechanical oscillators and the cavity on-resonance and thus create a dark mode by double sideband pumping of the cavity. We realize the scheme in a microwave optomechanical device employing two drum oscillators with unmatched frequencies, {\omega}_1 /2{\pi} = 8.1MHz and {\omega}_2 /2{\pi} = 14.2MHz. We also observe a breakdown of the rotating-wave approximation, most pronounced in another device where the mechanical frequencies are close to each other.