Multiband superconductors with degenerate excitation gaps
| Autor: | A. Vagov, Tiago T. Saraiva, M. D. Croitoru, J. Albino Aguiar, Paulo J. F. Cavalcanti, A. A. Shanenko |
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| Rok vydání: | 2020 |
| Předmět: |
Physics
Superconductivity Quantum Physics Condensed matter physics Condensed Matter - Superconductivity Degenerate energy levels FOS: Physical sciences 02 engineering and technology Fermion Electron 021001 nanoscience & nanotechnology Condensed Matter Physics 01 natural sciences Spectral line Superconductivity (cond-mat.supr-con) Electrical resistivity and conductivity Condensed Matter::Superconductivity 0103 physical sciences Density of states General Materials Science 010306 general physics 0210 nano-technology Quantum Physics (quant-ph) Excitation |
| DOI: | 10.48550/arxiv.2001.07531 |
| Popis: | There is a tacit assumption that multiband superconductors are essentially the same as multigap superconductors. More precisely, it is usually assumed that the number of excitation gaps in the single-particle energy spectrum of a uniform superconductor determines the number of contributing bands in the corresponding superconducting model. Here we demonstrate that contrary to this widely accepted viewpoint, the superconducting magnetic properties are sensitive to the number of contributing bands even when the corresponding excitation gaps are degenerate and cannot be distinguished. In particular, we find that the crossover between superconductivity types I and II - the intertype regime - is strongly affected by difference between characteristic lengths of multiple contributing condensates. The reason for this is that condensates with diverse characteristic lengths coexisting in one system interfere constructively or destructively, which results in multi-condensate magnetic phenomena regardless of the presence/absence of the multigap structure in the single-particle excitation spectrum. Comment: 13 pages and 2 figures |
| Databáze: | OpenAIRE |
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