Study of slow magnetization relaxation in Hf/GdFeCo/SiN Hall bar by anomalous Hall resistance measurements

• Published in: Journal of magnetism and magnetic materials Vol. 564; p. 170106
• Main Authors: Bhatt, Ramesh Chandra, Ye, Lin-Xiu, Lin, Li-Ren, Hai, Ngo Trong, Wu, Jong-Ching, Wu, Te-ho
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.12.2022
• Subjects: Anomalous Hall effect; Delayed propagation; GdFeCo; Magnetization relaxation; Notched Hall bar; Anomalous Hall effect; Delayed propagation; GdFeCo; Magnetization relaxation; Notched Hall bar
• ISSN: 0304-8853
• DOI: 10.1016/j.jmmm.2022.170106

•Magnetization relaxation in Hf/GdFeCo/SiN as a function of current polarity, probe widths, and notch in the device.•In notched Hall bar, the smaller HC for positive current seems due to valve-like behavior from notch.•Notch provides smaller delays for nucleation and switching compared to the no-notch Hall bar.•Narrow probe shows the advantage of comparatively faster and less stochastic switching.•Sense current is another important key to controlling the nucleation delay. The race-track memory concept relies on domain wall propagation through a magnetic track, which has the potential to change the future course of memory-related applications. Therefore, the materials where one can control the propagation of domain walls are crucial. Further, the stochastic nature of magnetization switching has potential applications in neuromorphic computing. Here we study the propagation of magnetic domains and the stochastic magnetization relaxation in the Gd-Fe-Co Hall bar. The magnetic relaxation of Hall bar devices is studied using anomalous Hall resistance measurements. This study highlights the behavior of magnetization relaxation under various parameters viz., at different magnitudes and directions of sensing currents, Hall probe aspect ratios, and the presence of a notch in the Hall bar. This study shows that the stochastic nature and delay in magnetization relaxation can be controlled by the sensing currents and the Hall bar geometry, which is crucial for magnetization switching-based applications.