Anomalous conductances in an ultracold quantum wire
Abstract
We analyze the recently measured anomalous transport properties of an ultracold gas through a ballistic constriction [S. Krinner et al., PNAS 201601812 (2016)]. The quantized conductance observed at weak interactions increases several-fold as the gas is made strongly interacting, which cannot be explained by the Landauer theory of single-channel transport. We show that this phenomenon is due to the multichannel Andreev reflections at the edges of the constriction, where the interaction and confinement result in a superconducting state. Andreev processes convert atoms of otherwise reflecting channels into the condensate propagating through the constriction, leading to a significant excess conductance. Furthermore, we find the spin conductance being suppressed by superconductivity; the agreement with experiment provides an additional support for our model.
Cite
@article{arxiv.1607.02509,
title = {Anomalous conductances in an ultracold quantum wire},
author = {Márton Kanász-Nagy and Leonid Glazman and Tilman Esslinger and Eugene A. Demler},
journal= {arXiv preprint arXiv:1607.02509},
year = {2016}
}
Comments
5 pages, 4 figures. Supplementary Material available as an ancillary file