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arXiv · 2108.03933

A generalized phenomenological model for the magnetic field penetration and magnetization hysteresis loops of a type-II superconductor

Wei Xie·Yu-Hao Liu·Hai-Hu Wen
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Abstract

A generalized phenomenological model for the critical state of type-II superconductors with magnetic field parallel to the superconducting plate is proposed. This model considers the global magnetization including both the equilibrium magnetization from surface screening current and the non-equilibrium magnetization from bulk pinning in a self-consistent way. Our model can be used to simulate the magnetization-hysteresis-loops (MHLs) and flux penetrating process of different type-II superconductors, from low- to high-kappa values. Here we take an optimally doped Ba0.6K0.4Fe2As2 single crystal as a testing example. The model can fit the data quite well and several important parameters can be extracted from the fitting. Thus, the model can be extended to a general case for studying the magnetization and flux penetration in other type-II superconductors.

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Wei Xie, Yu-Hao Liu, Hai-Hu Wen. 2021-08-09. A generalized phenomenological model for the magnetic field penetration and magnetization hysteresis loops of a type-II superconductor. https://doi.org/10.1103/physrevb.105.014505

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