Stability of a Bose-Einstein condensate in a driven optical lattice: Crossover between weak and tight transverse confinement

TL;DR

This paper investigates how transverse confinement influences the stability of a Bose-Einstein condensate in shaken optical lattices, identifying a critical confinement threshold for stability against decay due to collisions.

Contribution

It provides a theoretical analysis of the stability crossover in BECs under varying transverse confinement in driven optical lattices.

Findings

Existence of a critical transverse confinement for stability

Stability depends on shaking frequency and confinement strength

Predicted suppression of decay into transverse directions

Abstract

We explore the effect of transverse confinement on the stability of a Bose-Einstein condensate (BEC) loaded in a shaken one-dimensional or two-dimensional square lattice. We calculate the decay rate from two-particle collisions. We predict that if the transverse confinement exceeds a critical value, then, for appropriate shaking frequencies, the condensate is stable against scattering into transverse directions.