Anomalous vortex Hall effect in a ferromagnet/superconductor heterostructure

作     者：Sun, Weideng Swatek, Przemyslaw Fan, Yihong Yun, Hwanhui Lyu, Deyuan Mkhoyan, K. Andre Wang, Jian-Ping Qiu, Gang 

作者机构：Department of Electrical and Computer Engineering University of Minnesota Twin Cities MinneapolisMN55455 United States Department of Chemical Engineering and Materials Science University of Minnesota Twin Cities MinneapolisMN55455 United States Korea Research Institute of Chemical Technology Daejeon34114 Korea Republic of 

出 版 物：《arXiv》 (arXiv)

年 卷 期：2025年

核心收录：

主　　题：Magnetic fields 

摘      要：The coexistence of superconductivity and ferromagnetism is a fascinating and complex phenomenon in condensed matter physics, as these two states are typically mutually exclusive due to their competing spin configurations. However, the interplay between these two orders through the proximity effect has been a subject of intense research as it opens up possibilities for novel technological applications. Here, we report the coexistence of superconductivity and ferromagnetism in superconducting δ-TaN/ferromagnetic CoFeB heterostructures grown by facing-target sputtering. Superconducting states are comprehensively investigated, with evidence of strong correlation between the superconducting and ferromagnetic order parameters. In particular, we observed an anomalous Hall signal without the presence of the magnetic field in the mixed state of the superconducting transition near the critical temperature. Systematic characterizations of the Hall resistance under varying temperatures and magnetic fields attribute this behavior to the vortex Hall effect (VHE), whereby superconducting vortices in the mixed state undergo transverse motions near the critical temperature. Unlike previously reported VHEs in conventional type-II superconductors, the anomalous VHE in TaN is induced by the stray field in the underlying CoFeB layers. The concurrency of strong spin-orbit coupling, the superconductivity in the TaN layer, and the highly spin-polarized ferromagnetic ordering in the CoFeB layer offers new insights into proximity-induced vortex dynamics and the design of novel superconducting spintronic devices. Copyright © 2025, The Authors. All rights reserved.