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Superconducting Upper Critical Field Near a 2D Van Hove Singularity

R. G. Dias·J. M. Wheatley
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Abstract

The superconducting upper critical field $H_{c2}(T)$ of a two dimensional BCS superconductor is calculated in the vicinity of a van-Hove singularity. The zero temperature upper critical field is strongly enhanced at weak coupling when the Fermi contour coincides with van-Hove points, scaling as $H_{c2}(0) \propto T_c^{\sqrt{2}}$ compared to the usual result $H_{c2}(0) \propto T_c^{2}$. The result can be interpreted in terms of the non-Fermi liquid decay of normal state pair correlations in the vicinity of a van-Hove point.

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R. G. Dias, J. M. Wheatley. 1995-07-31. Superconducting Upper Critical Field Near a 2D Van Hove Singularity. https://doi.org/10.1016/0038-1098(96)00183-4

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