From semimetal to chiral Fulde-Ferrell superfluids

Abstract

The recent realization of two-dimensional (2D) synthetic spin-orbit (SO) coupling opens a broad avenue to study novel topological states for ultracold atoms. Here, we propose a new scheme to realize exotic chiral Fulde-Ferrell superfluid for ultracold fermions, with a generic theory being shown that the topology of superfluid pairing phases can be determined from the normal states. The main findings are two fold. First, a semimetal is driven by a new type of 2D SO coupling whose realization is even simpler than the recent experiment, and can be tuned into massive Dirac fermion phases with or without inversion symmetry. Without inversion symmetry the superfluid phase with nonzero pairing momentum is favored under an attractive interaction. Furthermore, we show a fundamental theorem that the topology of a 2D chiral superfluid can be uniquely determined from the unpaired normal states, with which the topological chiral Fulde-Ferrell superfluid with a broad topological region is predicted for the present system. This generic theorem is also useful for condensed matter physics and material science in search for new topological superconductors.

4 figures, 5 pages + Supplemenrary Material. Figures are updated, typos are corrected

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Cited by in corpus (11)

• Uncover Topology by Quantum Quench Dynamics
• Observation of symmetry-protected topological band with ultracold fermions
• Observation of nodal-line semimetal with ultracold fermions in an optical lattice
• Characterizing topological phases by quantum quenches: A general theory
• Spin-orbit coupling and topological phases for ultracold atoms
• Dynamically characterizing topological phases by high-order topological charges
• Fractional quantum anomalous Hall phase for Raman superarray of Rydberg atoms
• Larkin-Ovchinikov superfluidity in time-reversal symmetric bilayer Fermi gases
• Dynamical detection of mean-field topological phases in an interacting Chern insulator
• Generic reduction theory for Fermi sea topology in metallic systems
• Majorana Flat Bands in the Vortex Line of Superconducting Weyl Semimetals