Mixtures of fermionic atoms in an optical lattice

K. Ziegler

doi:10.1016/j.nuclphysa.2007.03.013

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Mixtures of fermionic atoms in an optical lattice

K. Ziegler

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Abstract

A mixture of light and heavy spin-polarized fermionic atoms in an optical lattice is considered. Tunneling of the heavy atoms is neglected such that they are only subject to thermal fluctuations. This results in a complex interplay between light and heavy atoms caused by quantum tunneling of the light atoms. The distribution of the heavy atoms is studied. It can be described by an Ising-like distribution with a first-order transition from homogeneous to staggered order. The latter is caused by an effective nonlocal interaction due to quantum tunneling of the light atoms. A second-order transition is also possible between an ordered and a disordered phase of the heavy atoms.

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K. Ziegler. 2006-11-01. Mixtures of fermionic atoms in an optical lattice. https://doi.org/10.1016/j.nuclphysa.2007.03.013

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