BCS-BEC Crossover in Two-Dimensional Attractive Hubbard Model under Magnetic Field

Abstract

The Bardeen-Cooper-Schrieffer (BCS)-Bose-Einstein condensation (BEC) crossover in the two-dimensional attractive Hubbard model under the magnetic field is discussed at the half-filling at T=0 K on the basis of the formalism of Eagles and Leggett. It is shown that the so-called Fulde-Ferrel-Larkin-Ovchinikov-like state with a non-zero center-of-mass wave vector $\mathbf{q}\ne 0$ is not stabilized in the weak-coupling (BCS) region, while such a state with $\mathbf{q}\ne 0$ is stabilized against that with $\mathbf{q}=0$ even in a wide strong-coupling (BEC) region where di-fermion molecules are formed. The physical implication of this surprising result is discussed.

arXiv comment10 pages, 7 figures

References in corpus (5)

• BCS-BEC Crossover: From High Temperature Superconductors to Ultracold Superfluids
• Inhomogeneous Superconductivity in Condensed Matter and QCD
• The BCS-BEC Crossover in a Gas of Fermi Atoms with a Feshbach Resonance
• Incommensurate magnetic order and phase separation in the two-dimensional Hubbard model with nearest and next-nearest neighbor hopping
• d-Wave Spin Density Wave phase in the Attractive Hubbard Model with Spin Polarization

Cited by in corpus (1)

• $\eta$-pairing on bipartite and non-bipartite lattices