Superfluid Dynamics with Cold Atoms: Quantum Turbulence and Entrainment

Khalid Hossain, Washington State University
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We will explore superfluid dynamics in a turbulent unitary Fermi gas (UFG), and a Fermi-Bose mixture using density functional theories.  These applications use cold atoms as quantum simulators for pulsar glitches.  We propose using a Fermi-Bose mixture to detect entrainment, important in explaining glitches -- a sudden increase in the rotation rate. If implemented, this will be the first direct detection of entrainment -- the modification of the flow in one superfluid in the presence of another. In addition, quantum turbulence is most likely an important part of glitches.  To understand the dynamics we time evolve a vortex tangle in a rotating UFG, and characterize different vortex tangle decay mechanisms.  Orbital-based simulations of fermions can be computationally challenging,  whereas an orbital-free theory is computationally less taxing and we found good agreement between the two. These calculations can potentially be simplified using machine learning, we will briefly discuss these possibilities as well.