Optical Lattices with Micromechanical Mirrors

TL;DR

This paper proposes a novel optomechanical system where atoms trapped in an optical lattice are coupled to a micro-membrane's vibrational mode, enabling sympathetic cooling and enhanced control over dissipation without optical cavities.

Contribution

It introduces a new setup with a micro-membrane and atomic cloud, demonstrating controllable dissipation and sympathetic cooling in free space, unlike traditional cavity-based systems.

Findings

Coupling of atomic center of mass to membrane vibrations predicted.

Significant sympathetic cooling effect of the membrane shown.

Enhanced dissipation control allows separation of cooling and coherent dynamics.

Abstract

We investigate a setup where a cloud of atoms is trapped in an optical lattice potential of a standing wave laser field which is created by retro-reflection on a micro-membrane. The membrane vibrations itself realize a quantum mechanical degree of freedom. We show that the center of mass mode of atoms can be coupled to the vibrational mode of the membrane in free space, and predict a significant sympathetic cooling effect of the membrane when atoms are laser cooled. The controllability of the dissipation rate of the atomic motion gives a considerable advantage over typical optomechanical systems enclosed in optical cavities, in that it allows a segregation between the cooling and coherent dynamics regimes. The membrane can thereby be kept in a cryogenic environment, and the atoms at a distance in a vacuum chamber.