Fraunhofer Patterns in Atomic Josephson Junctions

TL;DR

This paper demonstrates that synthetic magnetic fields can produce Fraunhofer-like interference patterns in atomic Josephson junctions, revealing unique features due to the superfluid's neutrality and advancing quantum technology applications.

Contribution

It introduces the concept of Fraunhofer pattern formation in atomic Josephson junctions under synthetic magnetic fields, highlighting distinctive interference effects.

Findings

Synthetic magnetic fields induce Fraunhofer-like critical current modulations.

Distinctive features arise from the neutral superfluid nature.

Numerical simulations reveal the role of Josephson vortices in current patterns.

Abstract

Driven atomic Josephson junctions allow one to monitor phase-coherent dynamics with unprecedented control and flexibility of the system's physical conditions. While cold-atom manifestations of the Josephson effect have been extensively studied in a wide variety of settings, atomic Josephson junctions in synthetic electromagnetic fields remain largely unexplored. Here, we show that synthetic magnetic fields can induce Fraunhofer-like modulations of the critical current in atomic Josephson junctions. Although this effect presents analogies to the Fraunhofer patterns found in superconducting devices, distinctive features emerge due to the neutral nature of the superfluid. We investigate the underlying spatial interference mechanisms and elucidate the role of Josephson vortices in the formation of spatially modulated current distributions based on numerical simulations. Our results open up new avenues for matter-wave circuits to deepen our understanding of spatial coherence in Josephson junctions, which are fundamental to the development of novel quantum technologies.