Chiral current of Bose-Einstein Condensates via asymmetric tunneling*

Tunnelling is one of the most well studied phenomena in quantum physics, and its implementations can be seen across many different fields. For example, the experimental creation of synthetic gauge fields, whose unique physics have opened new horizons in topological quantum matter and technology, is made much more complex due to the assumption that tunneling is symmetric. However, we computationally show the breaking of left-right tunneling symmetry using Bose-Einstein condensates (BEC) in 1D modeled by the Gross-Pitaevskii equation (GPE). These asymmetric tunneling dynamics suggests a simpler implementation for creating synthetic gauge fields: a trapped BEC in a quasi-1D ring-shaped potential comprised of periodic, asymmetric barriers. This trap exhibits left-right asymmetry in the transmission probability, thereby inducing a chiral motion of the BEC via directionally biased momentum. This is a signature of synthetic gauge fields, with the chiral current appearing as if it were induced by a magnetic field. Our computations employ experimentally feasible parameters such that these results may be experimentally demonstrated in the near future.