Magnetization of Flat Superconducting Films on Ferromagnetic Substrates

Leonid Prigozhin; Vladimir Sokolovsky

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arXiv · 2310.13475

Magnetization of Flat Superconducting Films on Ferromagnetic Substrates

Leonid Prigozhin·Vladimir Sokolovsky

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Abstract

Ferromagnetic substrate influences the electromagnetic response of a type-II superconducting film to the applied magnetic field. We present a two-dimensional integrodifferential model for the magnetization of a flat superconductor/ferromagnet bilayer of an arbitrary shape using a thin shell quasistatic model for the ferromagnetic substrate and an infinitely thin approximation for the superconducting layer. An efficient numerical method is developed and used to investigate the effect of a ferromagnetic substrate. In particular, we simulate the thin bilayer magnetization in a parallel field and, for a high field, the critical-state distributions of the superconducting current density. These critical-state distributions are different from those known for a normal external field.

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cond-mat.supr-con cs.NA math.NA

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Leonid Prigozhin, Vladimir Sokolovsky. 2023-10-20. Magnetization of Flat Superconducting Films on Ferromagnetic Substrates. https://arxiv.org/abs/2310.13475

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