Affiliation:
1. Graduate School and Faculty of Information Science and Electrical Engineering, Kyushu University , Fukuoka 819-0395, Japan
Abstract
In this study, we prepared a multi-layer Tb–Fe/Pt/Tb–Fe wire to develop a multi-level magnetic memory. By applying current, magnetizations of the Tb–Fe layers were inversion symmetrically switched by spin– orbit torque (SOT) generated from the middle Pt layer. Measurements of SOT showed that its efficiency had opposite polarities in the top and bottom Tb–Fe layers. The switching current density of the top and bottom Tb–Fe layers shifted in opposite directions under a uniform perpendicular magnetic field. Because the perpendicular magnetic field broke the inversion symmetry of SOT generated from the middle Pt layer, it could be used to control the switching current. Our results prove that the additional uniform and perpendicular magnetic field can enhance the controllability of the magnetization state in case of multi-level SOT-induced magnetization switching.
Funder
JSPS KAKENHI
Hattori Hokokai Foundation
JST ACT-X
Micron Technologies Foundation
Subject
General Physics and Astronomy