Vortex dipole precession in a Fermi superfluid with Rashba spin-orbit coupling

L. A. Toikka

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arXiv · 1711.04970

Vortex dipole precession in a Fermi superfluid with Rashba spin-orbit coupling

L. A. Toikka

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Abstract

We present a closed-form expression for the time dynamics of a balanced Fermi superfluid with s-wave pairing and Rashba spin-orbit (SO) coupling. Solving the associated self-consistency conditions for an initial number density given by a Gaussian and an initial gap containing a vortex dipole, we show that Rashba SO coupling results in precession of the vortex dipole. The integrated self-consistent gap decays as a function of time, characterising a "transient Fermi superfluid". Our analytic solution forms a starting point for studies of vortex dynamics -- in particular braiding of Majorana fermions -- in Fermi superfluids in the presence of spin population imbalance and two-dimensional SO coupling, which are both required to realize a topological atomic Fermi gas in experiments.

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L. A. Toikka. 2017-11-14. Vortex dipole precession in a Fermi superfluid with Rashba spin-orbit coupling. https://arxiv.org/abs/1711.04970

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