Exact pairing correlations for one-dimensionally trapped fermions with stochastic mean-field wave functions

Phys Rev Lett. 2004 Apr 23;92(16):160401. doi: 10.1103/PhysRevLett.92.160401. Epub 2004 Apr 19.

Abstract

The canonical thermodynamic properties of a one-dimensional system of interacting spin-1/2 fermions with an attractive zero-range pseudopotential are investigated within an exact approach. The density operator is evaluated as the statistical average of dyadics formed from a stochastic mean-field propagation of independent Slater determinants. For a harmonically trapped Fermi gas and for fermions confined in a 1D-like torus, we observe the transition to a quasi-BCS state with Cooper-like momentum correlations and an algebraic long-range order. For a few trapped fermions in a rotating torus, a dominant superfluid component with quantized circulation can be isolated.