Dissipative quantum dynamics of bosonic atoms in a shallow 1D optical lattice

TL;DR

This paper models the quantum dynamics of bosonic atoms in a shallow 1D optical lattice, revealing how quantum fluctuations induce dissipative transport even without thermal effects, aligning with recent experimental observations.

Contribution

It provides a theoretical explanation for dissipative atom transport in shallow lattices, emphasizing the role of quantum fluctuations and momentum uncertainty.

Findings

Quantum fluctuations generate atom populations in unstable velocity regions.

Dissipative transport occurs even at zero temperature.

Results align with recent experimental data.

Abstract

We theoretically study the dipolar motion of bosonic atoms in a very shallow, strongly confined 1D optical lattice using the parameters of the recent experiment [Fertig et al., Phys. Rev. Lett. 94, 220402 (2005)]. We find that, due to momentum uncertainty, a small, but non-negligible, atom population occupies the unstable velocity region of the corresponding classical dynamics, resulting in the observed dissipative atom transport. This population is generated even in a static vapor, due to quantum fluctuations which are enhanced by the lattice and the confinement, and is not notably affected by the motion of atoms or finite temperature.