A dipolar self-induced bosonic Josephson junction

TL;DR

This paper introduces a novel method to realize Josephson oscillations and self-trapping in a Bose-Einstein condensate using dipolar interactions to create a self-induced double-well potential in a toroidal trap.

Contribution

It demonstrates a new scheme for observing quantum tunneling phenomena in BECs through dipolar interactions creating a self-induced Josephson junction.

Findings

Coherent tunneling phenomena observed in simulations.

Self-induced double-well potential achieved via dipolar interactions.

Two-mode model effectively describes the dynamics.

Abstract

We propose a new scheme for observing Josephson oscillations and macroscopic quantum self-trapping phenomena in a toroidally confined Bose-Einstein condensate: a dipolar self-induced Josephson junction. Polarizing the atoms perpendicularly to the trap symmetry axis, an effective ring-shaped, double-well potential is achieved which is induced by the dipolar interaction. By numerically solving the three-dimensional time-dependent Gross-Pitaevskii equation we show that coherent tunneling phenomena such as Josephson oscillations and quantum self-trapping can take place. The dynamics in the self-induced junction can be qualitatively described by a two-mode model taking into account both s-wave and dipolar interactions.