Transition from Type-I to Type-II Superconducting Behaviour with Temperature observed by $μ$SR and SANS

C. M. Aegerter; H. Keller; S. L. Lee; C. Ager; F. Y. Ogrin; R. Cubitt; E. M. Forgan; W. J. Nutall; P. G. Kealey; S. H. Lloyd; S. T. Johnson; T. M. Riseman; M. P. Nutley

arXiv · cond-mat/0305595

Transition from Type-I to Type-II Superconducting Behaviour with Temperature observed by $μ$SR and SANS

C. M. Aegerter·H. Keller·S. L. Lee·C. Ager·F. Y. Ogrin·R. Cubitt·E. M. Forgan·W. J. Nutall·P. G. Kealey·S. H. Lloyd·S. T. Johnson·T. M. Riseman·M. P. Nutley

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Abstract

We investigate the superconducting behaviour of Bi doped Pb. Pure lead shows type-I behaviour entering an intermediate state in a magnetic field. High dopings of Bi ($>$3%) lead to type-II behaviour showing a mixed state, where the magnetic field penetrates the superconductor in the form of a flux lattice. At intermediate doping, the sample shows both type-I and type-II behaviour depending on the temperature. This arises because the Ginzburg-Landau parameter $κ$ passes through its critical value of $1/\sqrt{2}$ with temperature.

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C. M. Aegerter, H. Keller, S. L. Lee, C. Ager, F. Y. Ogrin, R. Cubitt, E. M. Forgan, W. J. Nutall, P. G. Kealey, S. H. Lloyd, S. T. Johnson, T. M. Riseman, M. P. Nutley. 2003-05-26. Transition from Type-I to Type-II Superconducting Behaviour with Temperature observed by $μ$SR and SANS. https://arxiv.org/abs/cond-mat/0305595

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