Cooling mechanical oscillators by coherent control

TL;DR

This paper demonstrates a method to cool mechanical oscillators by coherently coupling and controlling their energy transfer using optical fields, enabling advanced manipulation of mechanical systems.

Contribution

It introduces an optically controlled coupling between mechanical modes of a nanoparticle, enabling sympathetic cooling and coherent energy transfer.

Findings

Successfully cooled one mode via coupling to a feedback-cooled mode

Demonstrated coherent energy transfer between mechanical modes

Discussed potential for ground-state cooling applications

Abstract

In optomechanics, electromagnetic fields are harnessed to control a single mode of a mechanically compliant system, while other mechanical degrees of freedom remain unaffected due to the modes' mutual orthogonality and high quality factor. Extension of the optical control beyond the directly addressed mode would require a controlled coupling between mechanical modes. Here, we introduce an optically controlled coupling between two oscillation modes of an optically levitated nanoparticle. We sympathetically cool one oscillation mode by coupling it coherently to the second mode, which is feedback cooled. Furthermore, we demonstrate coherent energy transfer between mechanical modes and discuss its application for ground-state cooling.