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Confinement and Superfluidity in one-dimensional Degenerate Fermionic Cold Atoms

P. Lecheminant·E. Boulat·P. Azaria
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Abstract

The physical properties of arbitrary half-integer spins $F = N - 1/2$ fermionic cold atoms trapped in a one-dimensional optical lattice are investigated by means of a low-energy approach. Two different superfluid phases are found for $F \ge 3/2$ depending on whether a discrete symmetry is spontaneously broken or not: an unconfined BCS pairing phase and a confined molecular superfluid instability made of $2N$ fermions. We propose an experimental distinction between these phases for a gas trapped in an annular geometry. The confined-unconfined transition is shown to belong to the $Z_N$ generalized Ising universality class. We discuss on the possible Mott phases at $1/2N$ filling.

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P. Lecheminant, E. Boulat, P. Azaria. 2005-10-11. Confinement and Superfluidity in one-dimensional Degenerate Fermionic Cold Atoms. https://doi.org/10.1103/physrevlett.95.240402

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