Fulde-Ferrell-Larkin-Ovchinnikov pairing states of a polarized dipolar Fermi gas trapped in a one-dimensional optical lattice

TL;DR

This study investigates the phase diagram of a polarized dipolar Fermi gas in a 1D optical lattice, revealing that the FFLO pairing state persists despite long-range dipolar interactions, with detailed analysis of various quantum phases.

Contribution

It provides the first detailed phase diagram showing the coexistence and stability of FFLO and other states in a dipolar Fermi gas with long-range interactions.

Findings

FFLO state remains stable with long-range dipolar interactions

Phase diagram includes FFLO, half-metal, and normal states

Long-range interactions do not eliminate FFLO regions

Abstract

We study the interplay between the long- and short-range interaction of a one-dimensional optical lattice system of two-component dipolar fermions by using the density matrix renormalization group method. The atomic density profile, pairing-pairing correlation function, and the compressibility are calculated in the ground state, from which we identify the parameter region of the Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) pairing state, half-metal (HM) state, FFLO-HM state, and the normal polarized state, and thus the phase diagram in the coordinates of the long- and short-range interaction strength. The effect of the long-range dipolar interaction on the FFLO state is discussed in details. We find that the long-range part of the dipole-dipole interaction does not sweep away the FFLO superconducting region that is driven by the short-range interaction in the Hubbard model, and thus the FFLO state survives in the wide parameter space of the long-range interaction, polarization and the filling.