Josephson Current Flowing in Cyclically Coupled Bose-Einstein Condensates

TL;DR

This paper theoretically investigates the Josephson effect in cyclically coupled Bose-Einstein condensates, revealing how initial phases and coupling strength influence current flow, vortex formation, and transition to chaos, with implications for quantum fluid dynamics.

Contribution

It introduces a theoretical analysis of Josephson currents in cyclic BECs, highlighting phase-dependent current flow and the transition from periodic to chaotic dynamics as coupling varies.

Findings

Josephson current depends on initial phase differences.

Reducing coupling induces a transition from periodic to chaotic behavior.

Cyclic currents can lead to quantized vortex formation.

Abstract

The Josephson effect in cyclically coupled Bose-Einstein condensates is studied theoretically. We analyze the simultaneous Gross-Pitaevskii equations with coupling terms between adjacent condensates. Depending on the initial relative phases between condensates, Josephson current flows cyclically to make a quantized vortex. Reducing the coupling between condensates changes the motion from periodic to chaotic, thus suppressing the cyclic current. The relation to the Kibble-Zurek mechanism is discussed.