Modification of the Upper Critical Field in a Two-Band Superconductor

Victor K. Wong; C. C. Sung

doi:10.1103/PhysRevLett.19.1236

Modification of the Upper Critical Field in a Two-Band Superconductor

Victor K. Wong and C. C. Sung

Phys. Rev. Lett. 19, 1236 – Published 20 November 1967

Abstract

The upper critical field $H_{c 2}$ for a Type-II two-band superconductor is investigated in the pure limit. Near $T_{c}$ , $H_{c 2}$ is dominated by the $s$ band, whereas the thermodynamic properties are determined by the $d$ band. A modification to the Gor'kov theory is found for the ratio of $K_{1} (T)$ at $T = 0$ and $T = T_{c}$ . This result may explain the discrepancy between the one-band theory and experimental data.

Received 9 October 1967

DOI:https://doi.org/10.1103/PhysRevLett.19.1236

Authors & Affiliations

Victor K. Wong^* and C. C. Sung^†

Department of Physics, The Ohio State University, Columbus, Ohio

^*Research supported in part by the National Science Foundation, Grant No. GP-4579, through The Ohio State University Research Foundation.
^†Research supported in part by the Air Force Office of Scientific Research, U. S. Air Force, under AFOSR Grant No. AF-AFOSR-869-65, through The Ohio State University Research Foundation.