BCS-BEC crossover in three-dimensional Fermi gases with spherical spin-orbit coupling

Lianyi He; Xu-Guang Huang

doi:10.1103/physrevb.86.014511

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arXiv · 1202.1492

BCS-BEC crossover in three-dimensional Fermi gases with spherical spin-orbit coupling

Lianyi He·Xu-Guang Huang

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Abstract

We present a systematic theoretical study of the BCS-BEC crossover problem in three-dimensional atomic Fermi gases at zero temperature with a spherical spin-orbit coupling which can be generated by a synthetic non-Abelian gauge field coupled to neutral fermions. Our investigations are based on the path integral formalism which is a powerful theoretical scheme for the study of the properties of the bound state, the superfluid ground state, and the collective excitations in the BCS-BEC crossover. At large spin-orbit coupling, the system enters the BEC state of a novel type of bound state (referred to as rashbon) which possesses a non-trivial effective mass. Analytical results and interesting universal behaviors for various physical quantities at large spin-orbit coupling are obtained. Our theoretical predictions can be tested in future experiments of cold Fermi gases with three-dimensional spherical spin-orbit coupling.

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BibTeX RIS

Lianyi He, Xu-Guang Huang. 2012-02-07. BCS-BEC crossover in three-dimensional Fermi gases with spherical spin-orbit coupling. https://doi.org/10.1103/physrevb.86.014511

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