Accurate projective two-band description of topological superfluidity in spin-orbit-coupled Fermi gases

J. Brand; L. A. Toikka; U. Zülicke

doi:10.21468/scipostphys.5.2.016

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arXiv · 1803.05579

Accurate projective two-band description of topological superfluidity in spin-orbit-coupled Fermi gases

J. Brand·L. A. Toikka·U. Zülicke

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Abstract

The interplay of spin-orbit coupling and Zeeman splitting in ultracold Fermi gases gives rise to a topological superfluid phase in two spatial dimensions that can host exotic Majorana excitations. Theoretical models have so far been based on a four-band Bogoliubov-de Gennes formalism for the combined spin-1/2 and particle-hole degrees of freedom. Here we present a simpler, yet accurate, two-band description based on a well-controlled projection technique that provides a new platform for exploring analogies with chiral p-wave superfluidity and detailed future studies of spatially non-uniform situations.

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J. Brand, L. A. Toikka, U. Zülicke. 2018-03-15. Accurate projective two-band description of topological superfluidity in spin-orbit-coupled Fermi gases. https://doi.org/10.21468/scipostphys.5.2.016

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