Renormalization of Competing Interactions and Superconductivity on Small Scales |
| |
Authors: | A Aharony O Entin-Wohlman Y Imry |
| |
Institution: | 1. Department of Physics, Ben Gurion University, 84105, Beer Sheva, Israel 2. Raymond and Beverly Sackler School of Physics and Astronomy, Tel Aviv University, 69978, Tel Aviv, Israel 3. Department of Condensed Matter Physics, Weizmann Institute of Science, 76100, Rehovot, Israel
|
| |
Abstract: | The interaction-induced orbital magnetic response of a nanoscale ring is evaluated for a diffusive system which is a superconductor in the bulk. The interplay of the renormalized Coulomb and Fröhlich interactions is crucial. The magnetic susceptibility which results from the fluctuations of the uniform superconducting order parameter is diamagnetic (paramagnetic) when the renormalized combined interaction is attractive (repulsive). Above the transition temperature of the bulk the total magnetic susceptibility has contributions from many wave-vector- and (Matsubara) frequency-dependent order parameter fluctuations. Each of these contributions results from a different renormalization of the relevant coupling energy, when one integrates out the fermionic degrees of freedom. The total diamagnetic response of the large superconductor may become paramagnetic when the system’s size decreases. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|