Dynamics of interacting atoms in driven tilted optical lattices

TL;DR

This paper investigates how interactions affect the behavior of cold Bose atoms in driven tilted optical lattices, revealing phenomena like localization destruction and band collapse, with different spreading behaviors depending on driving resonance.

Contribution

It provides a detailed analysis of interaction effects on atom dynamics, including suppression of ballistic spreading and sub-diffusive spreading under various driving conditions.

Findings

Interaction suppresses ballistic spreading at resonance

Off-resonant driving leads to sub-diffusive spreading

Understanding experimental results requires accounting for interactions

Abstract

The dynamics of cold Bose atoms in driven tilted optical lattices is analyzed focusing on destruction of Wannier-Stark localization and the phenomenon of band collapse. It is argued that an understanding of the experimental results requires thorough account for interaction effects. These are suppression of the ballistic spreading of atoms for resonant driving (a multiple of the driving frequency coincides with the Bloch frequency) and unbounded sub-diffusive spreading of atoms for off-resonant driving.