Transitions and excitations in a superfluid stream passing small impurities
Abstract
We analyse asymptotically and numerically the motion around a single impurity and a network of impurities inserted in a two-dimensional superfluid. The criticality for the break down of superfluidity is shown to occur when it becomes energetically favourable to create a doublet - the limiting case between a vortex pair and a rarefaction pulse on the surface of the impurity. Depending on the characteristics of the potential representing the impurity different excitation scenarios are shown to exist for a single impurity as well as for a lattice of impurities. Depending on the lattice characteristics it is shown that several regimes are possible: dissipationless flow, excitations emitted by the lattice boundary, excitations created in the bulk and the formation of large scale structures.
Cite
@article{arxiv.1401.1517,
title = {Transitions and excitations in a superfluid stream passing small impurities},
author = {Florian Pinsker and Natalia G. Berloff},
journal= {arXiv preprint arXiv:1401.1517},
year = {2015}
}
Comments
submitted to Physical review A