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arXiv · 0801.1015

Noise correlations of the ultra-cold Fermi gas in an optical lattice

T. Paananen·T. K. Koponen·P. Torma·J. -P. Martikainen
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Abstract

In this paper we study the density noise correlations of the two component Fermi gas in optical lattices. Three different type of phases, the BCS-state (Bardeen, Cooper, and Schieffer), the FFLO-state (Fulde, Ferrel, Larkin, and Ovchinnikov), and BP (breach pair) state, are considered. We show how these states differ in their noise correlations. The noise correlations are calculated not only at zero temperature, but also at non-zero temperatures paying particular attention to how much the finite temperature effects might complicate the detection of different phases. Since one-dimensional systems have been shown to be very promising candidates to observe FFLO states, we apply our results also to the computation of correlation signals in a one-dimensional lattice. We find that the density noise correlations reveal important information about the structure of the underlying order parameter as well as about the quasiparticle dispersions.

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T. Paananen, T. K. Koponen, P. Torma, J. -P. Martikainen. 2008-04-23. Noise correlations of the ultra-cold Fermi gas in an optical lattice. https://doi.org/10.1103/physreva.77.053602

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