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Competing effects of mass anisotropy and spin Zeeman coupling on the upper critical field of a mixed $d$- and s-wave superconductor

Wonkee Kim·Jian-Xin Zhu·C. S. Ting
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Abstract

Based on the linearized Eilenberger equations, the upper critical field $(H_{c2})$ of mixed d- and s-wave superconductors has been microscopically studied with an emphasis on the competing effects of mass anisotropy and spin Zeeman coupling. We find the mass anisotropy always enhance $H_{c2}$ while the Zeeman interaction suppresses $H_{c2}$. As required by the thermodynamics, we find $H_{c2}$ is saturated at zero temperature. We compare the theoretical calculations with recent experimental data of YBa$_{2}$Cu$_{3}$O$_{7-+AFw-delta}$.

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Wonkee Kim, Jian-Xin Zhu, C. S. Ting. 1999-11-01. Competing effects of mass anisotropy and spin Zeeman coupling on the upper critical field of a mixed $d$- and s-wave superconductor. https://doi.org/10.1103/physrevb.61.4200

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