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Exact coherent states of a harmonically confined Tonks-Girardeau gas

A. Minguzzi·D. M. Gangardt
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Abstract

Using a scaling transformation we exactly determine the dynamics of an harmonically confined Tonks-Girardeau gas under arbitrary time variations of the trap frequency. We show how during a one-dimensional expansion a ``dynamical fermionization'' occurs as the momentum distribution rapidly approaches an ideal Fermi gas distribution, and that under a sudden change of the trap frequency the gas undergoes undamped breathing oscillations displaying alternating bosonic and fermionic character in momentum space. The absence of damping in the oscillations is a peculiarity of the truly Tonks regime.

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A. Minguzzi, D. M. Gangardt. 2005-06-27. Exact coherent states of a harmonically confined Tonks-Girardeau gas. https://doi.org/10.1103/physrevlett.94.240404

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