Exposing the quantum geometry of spin-orbit coupled Fermi superfluids

Abstract

The coupling between a quantum particle's intrinsic angular momentum and its center-of-mass motion gives rise to the so-called helicity states that are characterized by the projection of the spin onto the direction of momentum. In this paper, by unfolding the superfluid-density tensor into its intra-helicity and inter-helicity components, we reveal that the latter contribution is directly linked with the total quantum metric of the helicity bands. We consider both Rashba and Weyl spin-orbit couplings across the BCS-BEC crossover, and show that the geometrical inter-helicity contribution is responsible for up to a quarter of the total superfluid density. We believe this is one of those elusive effects that may be measured within the highly-tunable realm of cold Fermi gases.

6 pages with 4 figures; to appear in PRA

References in corpus (6)

• Band geometry, Berry curvature and superfluid weight
• Quantum metric contribution to the pair mass in spin-orbit coupled Fermi superfluids
• Geometric mass acquisition via quantum metric: an effective band mass theorem for the helicity bands
• Berezinskii-Kosterlitz-Thouless transition in the time-reversal-symmetric Hofstadter-Hubbard model
• Spin-susceptibility of spin-orbit coupled Fermi superfluids
• Geometrical effects in orbital magnetic susceptibility

Cited by in corpus (18)

• Semi-classical wave packet dynamics in non-uniform electric fields
• Extracting the Quantum Geometric Tensor of an Optical Raman Lattice by Bloch State Tomography
• Quantum Geometric Contributions to the BKT Transition: Beyond Mean Field Theory
• Quantum metric contribution to the pair mass in spin-orbit coupled Fermi superfluids
• Origin of flat-band superfluidity on the Mielke checkerboard lattice
• Pair Density Waves from Local Band Geometry
• Extracting quantum-geometric effects from Ginzburg-Landau theory in a multiband Hubbard model
• Anomalous Coherence Length in Superconductors with Quantum Metric
• Geometric superfluid weight of composite bands in multiorbital superconductors
• Geometric mass acquisition via quantum metric: an effective band mass theorem for the helicity bands
• Geometric contribution to the Goldstone mode in spin-orbit coupled Fermi superfluids
• Superfluid stiffness for the attractive Hubbard model on a honeycomb optical lattice
• Quantum-geometric perspective on spin-orbit-coupled Bose superfluids
• Quantum-geometric contribution to the Bogoliubov modes in a two-band Bose-Einstein condensate
• Superfluid weight and Berezinskii-Kosterlitz-Thouless temperature of spin-imbalanced and spin-orbit-coupled Fulde-Ferrell phases in lattice systems
• Superfluid weight cross-over and critical temperature enhancement in singular flat bands
• Spin-susceptibility of spin-orbit coupled Fermi superfluids
• Density matrix renormalization group study of quantum-geometry-facilitated pair density wave order