6 research outputs found
Limits of the upper critical field in dirty two-gap superconductors
An overview of the theory of the upper critical field in dirty two-gap
superconductors, with a particular emphasis on MgB is given. We focus here
on the maximum which may be achieved by increasing intraband
scattering, and on the limitations imposed by weak interband scattering and
paramagnetic effects. In particular, we discuss recent experiments which have
recently demonstrated ten-fold increase of in dirty carbon-doped films
as compared to single crystals, so that the parallel to the ab
planes may approach the BCS paramagnetic limit, . New effects produced by weak interband scattering in the two-gap
Ginzburg-Landau equations and in ultrathin MgB films are
addressed.Comment: Submitted to the special issue of Physica C on MgB on Dec. 3,
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