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arXiv · 1603.06054

Magnetic behaviour of dirty multiband superconductors near the upper critical field

Mikhail Silaev
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Abstract

Magnetic properties of dirty multiband superconductors near the upper critical field are studied. The parameter $κ_2$ characterizing magnetization slope is shown to have a significant temperature variation which is quite sensitive to the pairing interactions and relative strengths of intraband impurity scattering. In contrast to single-band superconductors the increase of $κ_2$ at low temperatures can be arbitrary large determined by the ratio of minimal and maximal diffusion coefficients in different bands. Temperature dependencies of $κ_2(T)$ in two-band MgB$_2$ and iron-based superconductors are shown to be much more sensitive to the multiband effects than the upper critical field $H_{c2}(T)$.

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Mikhail Silaev. 2016-03-19. Magnetic behaviour of dirty multiband superconductors near the upper critical field. https://doi.org/10.1103/physrevb.93.214509

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