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Upper critical field in {Ba$_{1-x}$K$_x$BiO$_3$}: magnetotransport versus magnetotunneling

P. Samuely·P. Szabo·T. Klein·A. G. M. Jansen·J. Marcus·C. Escribe-Filippini·P. Wyder
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Abstract

Elastic tunneling is used as a powerful direct tool to determine the upper critical field $H_{c2}(T)$ in the high-$T_c$ oxide Ba$_{1-x}$K$_x$BiO$_3$. The temperature dependence of $H_{c2}$ inferred from the tunneling follows the Werthamer-Helfand-Hohenberg prediction for type-II superconductors. A comparison will be made with resistively determined critical field data.

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P. Samuely, P. Szabo, T. Klein, A. G. M. Jansen, J. Marcus, C. Escribe-Filippini, P. Wyder. 2001-03-08. Upper critical field in {Ba$_{1-x}$K$_x$BiO$_3$}: magnetotransport versus magnetotunneling. https://doi.org/10.1209/epl%2Fi1998-00132-1

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