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arXiv · 1208.5640

Breathing mode of two-dimensional atomic Fermi gases in harmonic traps

Chao Gao·Zhenhua Yu
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Abstract

For two-dimensional (2D) atomic Fermi gases in harmonic traps, the SO(2,1) symmetry is broken by the interatomic interaction explicitly via the contact correlation operator. Consequently the frequency of the breathing mode $ω_B$ of the 2D Fermi gas can be different from $2ω_0$, with $ω_0$ the trapping frequency of harmonic potentials. At zero temperature, we use the sum rules of density correlation functions to yield upper bounds for $ω_B$. We further calculate $ω_B$ through the Euler equations in the hydrodynamic regime. The obtained value of $ω_B$ satisfies the upper bounds and shows deviation from $2ω_0$ which can be as large as about 8%.

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Chao Gao, Zhenhua Yu. 2012-08-28. Breathing mode of two-dimensional atomic Fermi gases in harmonic traps. https://doi.org/10.1103/physreva.86.043609

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