Dissipative dynamics of atomic Hubbard models coupled to a phonon bath: Dark state cooling of atoms within a Bloch band of an optical lattice

TL;DR

This paper proposes a novel laser-assisted cooling method for atoms in an optical lattice by coupling them to a BEC reservoir, enabling effective cooling within the Bloch band through a many-body open quantum system approach.

Contribution

It introduces a new cooling scheme that replaces traditional photon emission with BEC excitations, extending laser cooling concepts to lattice-confined atoms coupled to a reservoir.

Findings

Achieves temperatures below a fraction of the Bloch band width.

Applicable to both bosons and fermions in optical lattices.

Provides a theoretical framework for many-body open quantum systems.

Abstract

We analyse a laser assisted sympathetic cooling scheme for atoms within the lowest Bloch band of an optical lattice. This scheme borrows ideas from sub-recoil laser cooling, implementing them in a new context in which the atoms in the lattice are coupled to a BEC reservoir. In this scheme, excitation of atoms between Bloch bands replaces the internal structure of atoms in normal laser cooling, and spontaneous emission of photons is replaced by creation of excitations in the BEC reservoir. We analyse the cooling process for many bosons and fermions, and obtain possible temperatures corresponding to a small fraction of the Bloch band width within our model. This system can be seen as a novel realisation of a many-body open quantum system.