Magnetization suppression of Type-II Superconductors by external alternating magnetic field

TL;DR

This paper provides a theoretical analysis of how an external alternating magnetic field suppresses the static magnetization in anisotropic Type-II superconductors, revealing nonmonotonic behavior and conditions for complete suppression.

Contribution

It introduces a theoretical model describing magnetization suppression dynamics and calculates the critical field amplitude for complete suppression based on anisotropy and orientation.

Findings

Magnetization can vary nonmonotonically with increasing alternating field amplitude.

Transition from paramagnetic to diamagnetic state can be induced by the alternating field.

Critical amplitude for complete magnetization suppression depends on anisotropy and orientation.

Abstract

The effect of suppression of static magnetization of an anisotropic hard superconductor by alternating magnetic field is analyzed theoretically. The magnetic moment suppression dynamics is described with respect to the magnetization loop of the superconductor. It is found that in some cases the magnetic moment varies nonmonotonically with the growth in amplitude $\mathrm{h}$ of the alternating field. Effect of transition, induced by $\mathrm{\mathbf{h}}(t)$, of superconductor form paramagnetic into the diamagnetic state is considered. The amplitude of alternating magnetic field $\mathrm{h}_{c}(\delta,\vartheta)$ for which the complete suppression of the magnetization occurs is calculated as the function of anisotropy parameter $\delta$ and it orientation angle $\vartheta$ with respect to the crystallographic axes of the sample.