Instabilities and Transport in a Phase-Wound BEC in an Elongated Trap*

Two component Bose-Einstein condensates provide a finely controllable platform for investigating classical and quantum hydrodynamics. Analogues to classical hydrodynamic instabilities are known to appear in two-component superfluids, and such instabilities in the nuclear superfluid within a neutron star may be related to the unexplained phenomenon of pulsar glitches. These may coexist alongside phenomena with no classical analogue, such as the Countersuperflow instability or Josephson effect. In this work, we explore quantum and classical hydrodynamics in a phase-wound BEC in an elongated trap.