Tunability of the critical-current density in superconductor-ferromagnet hybrids

Abstract

Important modifications on the magnetization loops of the superconductor have been observed in superconductor-ferromagnet hybrids due to the effects of the ferromagnetic components, which can be used for tuning the superconductor critical-current density Jc to desirable values. Here, a model based on an energy minimization procedure is presented to analyze the complex interaction between the superconductor and the ferromagnets. We show how the geometry and orientation of the ferromagnets can be chosen for shifting the position of the peaks appearing in the magnetization to positive or negative applied fields, and, consequently, to tune Jc in superconductor-ferromagnet hybrids.

Calculation of AC loss in coated conductor coils with a large number of turns

“…The results of MMEV agree with experiments for coils [6,10]. Additionally, MMEV has been applied to model levitation [25,26]. The method has also been extended to take into account the interaction of the superconductor with linear magnetic materials [27].…”

Diamond magnetometry of Meissner currents in a superconducting film

“…25,26 More recently, however, various types of dependencies J c (B) have been assumed, and the calculation of the current density has been generalized accordingly. [54][55][56][57] In the so-called exponential model 27,58 J c (B(x)) is taken to be given by…”

Imaging the Statics and Dynamics of Superconducting Vortices and Antivortices Induced by Magnetic Microdisks

“…The inevitable transformation of the magnet's continuous stray field outside the superconductor into quantum flux-line bundles inside the superconductor gives rise to several interesting properties such as topological instabilities in superconductor-ferromagnet bilayers [2], field-induced superconductivity [3], domain-wall superconductivity [4], composite self-organized critical states [5,6], or quantized levitation height [7,8]. It is also crucial to take into consideration the interaction of quantized flux lines with ferromagnets in order to understand more practical systems such as magnetic force microscopy measurements of superconducting samples [9,10], the enhancement of the superconducting critical current in superconductorferromagnet hybrid systems [11][12][13][14], or why superconducting levitating trains do not derail in sharp curves [15,16].…”