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arXiv · 2203.06927

Asymmetry and nonlinearity of current-bias characteristics in superfluid-normal state junctions of weakly-interacting Bose gases

Shun Uchino
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Abstract

We uncover current-bias characteristics of superfluid-normal state junctions with weakly-interacting Bose gases. It is shown that in the presence of a chemical potential bias the characteristics can strongly be asymmetric for origin. The salient feature that is absent in the fermionic counterpart arises from a tunneling process associated with a condensate and a bosonic Andreev reflection process. It turns out that such processes are intrinsically nonlinear and therefore do not obey Ohm's law even at a low bias. In addition, the remaining processes are found to obey Ohm's law and become dominant for transport driven by a temperature bias.

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Shun Uchino. 2022-07-27. Asymmetry and nonlinearity of current-bias characteristics in superfluid-normal state junctions of weakly-interacting Bose gases. https://doi.org/10.1103/physreva.106.l011303

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