2020/01/21 by Paulo José Fonseca Cavalcanti, Paulo J. F. Cavalcanti, Cavalcanti, Paulo J. F. +11
Materials Science · Physics and Astronomy · #FOS: Physical sciences #Iron-based superconductors research #Magnetic and transport properties of perovskites and related materials #Physics of Superconductivity and Magnetism #Quantum Physics (quant-ph) #Superconductivity (cond-mat.supr-con) #cond-mat.supr-con #quant-ph
paper · pdf · doi:10.48550/arxiv.2001.07531
13 pages and 2 figures
arxiv created 2020/01/21 · openalex publication_date 2020/01/21 · arxiv updated 2020/01/22 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/01
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.