Physics

Fermion Pairing in Flatland

Mohit Randeria

Published Jan 23, 2012• 10 citations

Abstract

We follow the evolution of fermion pairing in the dimensional crossover from three-dimensional to twodimensional as a strongly interacting Fermi gas of 6 Li atoms becomes confined to a stack of twodimensional layers formed by a one-dimensional optical lattice.Decreasing the dimensionality leads to the opening of a gap in radio-frequency spectra, even on the Bardeen-Cooper-Schrieffer side of a Feshbach resonance.The measured binding energy of fermion pairs closely follows the theoretical two-body binding energy and, in the two-dimensional limit, the zero-temperature mean-field Bose-Einstein-condensation to Bardeen-Cooper-Schrieffer crossover theory.

DOI: 10.1103/physics.5.10

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