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arXiv · 1604.06063

Fermi Gases in the Two-Dimensional to Quasi-Two-Dimensional Crossover

Chingyun Cheng·J. Kangara·I. Arakelyan·J. E. Thomas
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Abstract

We tune the dimensionality of pancake-shaped strongly-interacting $^6$Li Fermi gas clouds from two-dimensional (2D) to quasi-2D, by controlling the ratio of the radial Fermi energy $E_F$ to the harmonic oscillator energy $h\nu_z$ in the tightly confined direction. In the 2D regime, where $E_F<<h\nu_z$, the measured radio frequency resonance spectra are in agreement with 2D-BCS theory. In the quasi-2D regime, where $E_F\simeq h\nu_z$, the measured spectra deviate significantly from 2D-BCS theory. For both regimes, the measured cloud radii disagree with 2D-BCS mean field theory, but agree approximately with predictions using a free energy derived from the Bethe-Goldstone equation.

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Chingyun Cheng, J. Kangara, I. Arakelyan, J. E. Thomas. 2016-04-20. Fermi Gases in the Two-Dimensional to Quasi-Two-Dimensional Crossover. https://doi.org/10.1103/physreva.94.031606

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