Upper Critical Field Peculiarities of Superconductingand
- 23 February 1998
- journal article
- Published by American Physical Society (APS) in Physical Review Letters
- Vol. 80 (8), 1730-1733
- https://doi.org/10.1103/physrevlett.80.1730
Abstract
We present new upper critical field Hc2(T) data in a broad temperature region from 0.3K to Tc for LuNi2B2C and YNi2B2C single crystals with well characterized low impurity scattering rates. The absolute values for all T, in particular Hc2(0), and the sizeable positive curvature (PC) of Hc2(T) at high and intermediate T are explained quantitatively within an effective two-band model. The failure of the isotropic single band approach is discussed in detail. Supported by de Haas van Alphen data, the superconductivity reveals direct insight into details of the electronic structure. The observed maximal PC near Tc gives strong evidence for clean limit type II superconductors.Comment: 4 pages, 2 figures, Phys. Rev. Lett. accepteThis publication has 32 references indexed in Scilit:
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