Zhai, H.Umucalılar, R. O.Oktel, M. Ö.2016-02-082016-02-0820100031-9007http://hdl.handle.net/11693/22357We study the structure of a pairing order parameter for spin-1/2 fermions with attractive interactions in a square lattice under a uniform magnetic field. Because the magnetic translation symmetry gives a unique degeneracy in the single-particle spectrum, the pair wave function has both zero and finite-momentum components coexisting, and their relative phases are determined by a self-consistent mean-field theory. We present a microscopic calculation that can determine the vortex lattice structure in the superfluid phase for different flux densities. Phase transition from a Hofstadter insulator to a superfluid phase is also discussed.EnglishFlux densitiesHofstadterInteracting fermionsMagnetic translationOptical latticesOrder parameterRelative phasisSelf-consistent mean-field theoriesSingle particle spectrumSpin-1/2 fermionsSquare latticesSuperfluid phaseVortex lattice structureVortex latticesCrystal latticesFermionsMagnetic fieldsMean field theoryNeodymium compoundsWave functionsPhase transitionsArticle10.1103/PhysRevLett.104.145301