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arXiv · 0712.2128

Functional-integral representation of atomic mixtures

O. Fialko·K. Ziegler
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Abstract

A mixture of spin-1/2 fermionic atoms and molecules of paired fermionic atoms is studied in an optical lattice. The molecules are formed by an attractive nearest-neighbor interaction. A functional integral is constructed for this many-body system and analyzed in terms of a mean-field approximation and Gaussian fluctuations. This provides a phase diagram with the two merging Mott insulators and an intermediate superfluid. The Gaussian fluctuations give rise to an induced repulsive dimer-dimer interaction mediated by the unpaired fermions. The effect of an unbalanced distribution of spin-up and spin-down fermions is also discussed.

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O. Fialko, K. Ziegler. 2007-12-13. Functional-integral representation of atomic mixtures. https://doi.org/10.1142/9789812837271_0054

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