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

Link:
Autor/in:
Erscheinungsjahr:
2017
Medientyp:
Text
Schlagworte:
  • Superconductors (materials)
  • Fermions
  • Topological superconducting
  • Insulators
  • Quantum Dots
  • Spin
  • Superconductors (materials)
  • Fermions
  • Topological superconducting
  • Insulators
  • Quantum Dots
  • Spin
Beschreibung:
  • 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 Dpoint-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 Zsymmetry of these odd-parity superfluids, we infer their topological features simply from the symmetry and the Fermi-surface topology as confirmed numerically.
Lizenz:
  • info:eu-repo/semantics/restrictedAccess
Quellsystem:
Forschungsinformationssystem der UHH

Interne Metadaten
Quelldatensatz
oai:www.edit.fis.uni-hamburg.de:publications/4e2033e1-5167-4807-a564-c5960a448184