Spin-orbit-coupled topological Fulde-Ferrell states of fermions in a harmonic trap

Published

November 7, 2014

Author(s)

Lei Jiang, Eite Tiesinga, Xie-Ji Liu, Hui Hu, Han Pu

Abstract

Motivated by recent experimental breakthroughs in generating spin-orbit coupling in ultracold Fermi gases using Raman laser beams, we present a systematic study of spin-orbit-coupled Fermi gases confined in a quasi-one-dimensional trap in the presence of an in-plane Zeeman field (which can be realized using a finite two-photon Raman detuning). We find that a topological Fulde-Ferrell state will emerge, featuring finite-momentum Cooper pairing and zero-energy Majorana excitations localized near the edge of the trap based on the self-consistent Bogoliubov-de Genes (BdG) equations. We find analytically the wavefunctions of the Majorana modes. Finally using the time-dependent BdG we show how the finite-momentum pairing field manifests itself in the expansion dynamics of the atomic cloud.

Citation

Physical Review A (Atomic, Molecular and Optical Physics)

Volume

90

Issue

5

Pub Type

Journals

Download Paper

https://doi.org/10.1103/PhysRevA.90.053606

Local Download

Keywords

Fermi gas, spin-orbit coupling, Fulde-Ferrell superfluid

Citation

Jiang, L. , Tiesinga, E. , Liu, X. , Hu, H. and Pu, H. (2014), Spin-orbit-coupled topological Fulde-Ferrell states of fermions in a harmonic trap, Physical Review A (Atomic, Molecular and Optical Physics), [online], https://doi.org/10.1103/PhysRevA.90.053606, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=916322 (Accessed September 9, 2024)