1999/10/04 by I. S. Beloborodov, K. B. Efetov, A. I. Larkin · 44 citations
Physics and Astronomy · #Advanced Condensed Matter Physics #Condensed matter physics #Coulomb #Electrical resistivity and conductivity #Electron #Field (mathematics) #Magnetic field #Magnetoresistance #Materials science #Physics #Physics of Superconductivity and Magnetism #Quantum mechanics #Rare-earth and actinide compounds #Superconductivity #cond-mat.mes-hall #cond-mat.supr-con
paper · pdf · doi:10.1103/physrevb.61.9145
published in Physical review. B, Condensed matter 61(13), 9145-9161 (American Physical Society) · 24 pages, 10 figures
arxiv created 1999/10/04 · openalex publication_date 2000/04/01 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
The magnetoresistance of a granular superconductor in a strong magnetic field is considered. It is assumed that this field destroys the superconducting gap in each grain, such that all interesting effects considered in the paper are due to superconducting fluctuations. The conductance of the system is assumed to be large, which allows us to neglect all localization effects as well as the Coulomb interaction. It is shown that at low temperatures the superconducting fluctuations reduce the one-particle density of states but do not contribute to transport. As a result, the resistivity of the normal state exceeds the classical resistivity approaching the latter only in the limit of extremely strong magnetic fields, and this leads to a negative magnetoresistance. We present detailed calculations of physical quantities relevant for describing the effect and make a comparison with existing experiments.