Physics of Narrow Superconducting and Superfluid Channels: Critical Temperature and Associated Single Vortices Nucleation

M. B. Sobnack, F. V. Kusmartsev

Research output: Contribution to journalConference articlepeer-review

Abstract

It is well known that in lower dimensions at any finite temperature one can thermally create single vortex excitations. This is because the boundary cut-off eliminates the logarithmic divergence of the vortex energy, thus eliminating the Berezinsk-Kosterlitz-Thouless transition which typically exists in 2D films. However, single vortices created in a channel are strongly attracted to the boundaries; as a result, their life-time is very short. Here we demonstrate that with rising temperature the density of spontaneously generated vortices and anti-vortices increases significantly faster than one would expect from conventional activation law. The two boundaries of the channels act as mirrors that multiply the effective number of vortices and anti-vortices spontaneously created and makes it practically equal to infinity. All these vortices, a few real bare and infinitely many imaginary ones, screen the vortex-vortex and vortex-boundary interactions. As a result of the screening, the life-time and density of vortices increase. This process constitutes a new mechanism for the destruction of phase coherence, superconductivity or superfluidity in narrow channels. We describe this effect using real space renormalization group techniques and derive an expression for the scale-dependent critical temperature at which the vortices destroy superconductivity/superfluidity in a cascade manner.

Original languageBritish English
Article number012003
JournalJournal of Physics: Conference Series
Volume1041
Issue number1
DOIs
StatePublished - 12 Jun 2018
Event19th International Conference Recent Progress in Man-Body Theories, RPMBT 2017 - Pohang, Korea, Republic of
Duration: 25 Jun 201730 Jun 2017

Fingerprint

Dive into the research topics of 'Physics of Narrow Superconducting and Superfluid Channels: Critical Temperature and Associated Single Vortices Nucleation'. Together they form a unique fingerprint.

Cite this