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arXiv · 2007.03061

Four-fold anisotropy of the parallel upper critical magnetic field in a pure layered d-wave superconductor at $T = 0$

Andrei G. Lebed
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Abstract

It is well known that a four-fold symmetry of the parallel upper critical magnetic field disappears in the Ginzburg-Landau (GL) region in quasi-two-dimensional (Q2D) $d$-wave superconductors. Therefore, it has been accurately calculated so far as a correction to the GL results, which is valid close to superconducting transition temperature and is expected to be stronger at low temperatures. As to the case $T=0$, some approximated methods have been used, which are good only for closed electron orbits and unappropriate for the open orbits which exist in a parallel magnetic field in Q2D superconductors. For the first time, we accurately calculate the four-fold anisotropy of the parallel upper critical magnetic field in a pure Q2D $d$-wave superconductor at $T=0$, where it has the highest possible value. Our results are applicable to Q2D $d$-wave high-Tc and organic superconductors.

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Andrei G. Lebed. 2020-07-06. Four-fold anisotropy of the parallel upper critical magnetic field in a pure layered d-wave superconductor at $T = 0$. https://doi.org/10.1134/s0021364020040037

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