Self-trapping of Bose-Einstein condensates in optical lattices

TL;DR

This paper investigates the phenomenon of self-trapping in Bose-Einstein condensates within optical lattices through numerical simulations, revealing its temporary nature and linking it to double-well potential dynamics.

Contribution

It demonstrates that self-trapping in optical lattices is only temporary and connects it to double-well potential phenomena, providing new insights into BEC dynamics.

Findings

Self-trapping is temporary and breaks down at long times.

Numerical results reproduce experimental observations.

Self-trapping relates to double-well potential dynamics.

Abstract

The self-trapping phenomenon of Bose-Einstein condensates (BECs) in optical lattices is studied extensively by numerically solving the Gross-Pitaevskii equation. Our numerical results not only reproduce the phenomenon that was observed in a recent experiment [Anker {\it et al.}, Phys. Rev. Lett. {\bf 94} (2005)020403], but also find that the self-trapping breaks down at long evolution times, that is, the self-trapping in optical lattices is only temporary. The analysis of our numerical results shows that the self-trapping in optical lattices is related to the self-trapping of BECs in a double-well potential. A possible mechanism of the formation of steep edges in the wave packet evolution is explored in terms of the dynamics of relative phases between neighboring wells.