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Superfluidity versus Bloch oscillations in confined atomic gases

H. P. Büchler·V. B. Geshkenbein·G. Blatter
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Abstract

We study the superfluid properties of (quasi) one-dimensional bosonic atom gases/liquids in traps with finite geometries in the presence of strong quantum fluctuations. Driving the condensate with a moving defect we find the nucleation rate for phase slips using instanton techniques. While phase slips are quenched in a ring resulting in a superfluid response, they proliferate in a tube geometry where we find Bloch oscillations in the chemical potential. These Bloch oscillations describe the individual tunneling of atoms through the defect and thus are a consequence of particle quantization.

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H. P. Büchler, V. B. Geshkenbein, G. Blatter. 2001-05-02. Superfluidity versus Bloch oscillations in confined atomic gases. https://doi.org/10.1103/physrevlett.87.100403

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