Coherent mechanical noise cancellation and cooperativity competition in optomechanical arrays

TL;DR

This paper demonstrates how optomechanical arrays can coherently cancel mechanical thermal noise and reveals a collective effect where the coupling of one resonator influences the dissipation of another.

Contribution

It introduces a method for noise cancellation via optomechanical phase lag and uncovers a new collective phenomenon called cooperativity competition in coupled resonators.

Findings

Thermal noise can be cancelled by up to 20 dB through optomechanical phase lag.

The cavity induces a controllable time delay affecting noise interference.

Coupling efficiency of one resonator influences the linewidth of another.

Abstract

Studying the interplay between multiple coupled mechanical resonators is a promising new direction in the field of optomechanics. Understanding the dynamics of the interaction can lead to rich new effects, such as enhanced coupling and multi-body physics. In particular, multi-resonator optomechanical systems allow for distinct dynamical effects due to the optical cavity coherently coupling mechanical resonators. Here, we study the mechanical response of two SiN membranes and a single optical mode, and find that the cavity induces a time delay between the local and cavity-transduced thermal noises experienced by the resonators. This results in an optomechanical phase lag that causes destructive interference, cancelling the mechanical thermal noise by up to 20 dB in a controllable fashion, matching our theoretical expectation. Based on the effective coupling between membranes, we further propose, derive and measure a collective effect, cooperativity competition on mechanical dissipation, whereby the linewidth of one resonator depends on the coupling efficiency (cooperativity) of the other resonator.