arXiv:cond-mat/0401643 · Physical Review Letters

Insulating Behavior of a Trapped Ideal Fermi Gas

Luca Pezzè, Лев П. Питаевский, Augusto Smerzi, S. Stringari, Giovanni Carlo Modugno, Estefania de Mirandés, Francesca Ferlaino, Herwig Ott, G. Roati, M. Inguscio

Published Sep 13, 2004• 93 citations

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Abstract

We investigate theoretically and experimentally the center-of-mass motion of an ideal Fermi gas in a combined periodic and harmonic potential. We find a crossover from a conducting to an insulating regime as the Fermi energy moves from the first Bloch band into the band gap of the lattice. The conducting regime is characterized by an oscillation of the cloud about the potential minimum, while in the insulating case the center of mass remains on one side of the potential.

DOI: 10.1103/physrevlett.93.120401

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