Odd-parity topological superfluidity for fermions in a bond-centered square optical lattice

Abstract

We propose a physical scheme for the realization of two-dimensional topological odd-parity superfluidity in a spin-independent bond-centered square optical lattice based upon interband fermion pairing. The D4 point-group symmetry of the lattice protects a quadratic band crossing, which allows one to prepare a Fermi surface of spin-up fermions with odd parity close to the degeneracy point. In the presence of spin-down fermions with even parity populating a different energetically well separated band, odd-parity pairing is favored. Strikingly, as a necessary prerequisite for pairing both Fermi surfaces can be tuned to match well. As a result, topological superfluid phases emerge in the presence of merely s-wave interaction. Due to the Z2 symmetry of these odd-parity superfluids, we infer their topological features simply from the symmetry and the Fermi-surface topology as confirmed numerically.

arXiv comment6+7 pages, 3+6 figures

References in corpus (36)

• Non-Abelian Anyons and Topological Quantum Computation
• Superconducting proximity effect and Majorana fermions at the surface of a topological insulator
• Paired states of fermions in two dimensions with breaking of parity and time-reversal symmetries, and the fractional quantum Hall effect
• Topological superconductors: a review
• Pairing and Phase Separation in a Polarized Fermi Gas
• Fermionic Superfluidity with Imbalanced Spin Populations and the Quantum Phase Transition to the Normal State
• Odd-Parity Topological Superconductors: Theory and Application to Cu${}_x$Bi${}_2$Se${}_3$
• Non-Abelian Topological Order in S-Wave Superfluids of Ultracold Fermionic Atoms
• Majorana mode in vortex core of Bi2Te3/NbSe2 topological insulator-superconductor heterostructure
• The Coexistence of Superconductivity and Topological Order in the Bi2Se3 Thin Films
• Spin-Imbalance in a One-Dimensional Fermi Gas
• Ultracold Atoms in a Tunable Optical Kagome Lattice
• Topological Insulators and Nematic Phases from Spontaneous Symmetry Breaking in 2D Fermi Systems with a Quadratic Band Crossing
• Resonantly-paired fermionic superfluids
• $p_x+i{p}_y$ superfluid from s-wave interactions of fermionic cold atoms
• A lattice of double wells for manipulating pairs of cold atoms
• Evidence for Superfluidity of Ultracold Fermions in an Optical Lattice
• Coherent driving and freezing of bosonic matter wave in an optical Lieb lattice
• Orbital superfluidity in the $P$-band of a bipartite optical square lattice
• Multi-Component Quantum Gases in Spin-Dependent Hexagonal Lattices
• Chiral P-Wave Order in Sr_2RuO_4
• Topological odd-parity superconductors
• Homogeneous Atomic Fermi Gases
• Realization of 2D Spin-orbit Interaction and Exotic Topological Orders in Cold Atoms
• Stable Topological Superfluid Phase of Ultracold Polar Fermionic Molecules
• Topological semimetal in a fermionic optical lattice
• Artificial graphene with tunable interactions
• Tomographic RF Spectroscopy of a Trapped Fermi Gas at Unitarity
• Majorana modes and $p$-wave superfluids for fermionic atoms in optical lattices
• Superfluid-Insulator Transition of Strongly Interacting Fermi Gases in Optical Lattices
• Topological superfluid in a Fermi-Bose mixture with a high critical temperature
• Superfluid-insulator transitions of the Fermi gas with near-unitary interactions in a periodic potential
• $p$-wave chiral superfluidity from an $s$-wave interacting atomic Fermi gas
• π-flux Dirac bosons and topological edge excitations in a bosonic chiral p-wave superfluid
• Chiral d-wave superfluid in periodically driven lattices
• Effective p-wave interaction and topological superfluids in s-wave quantum gases

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