Junior students Chen Zehan and Liu Lin from College of New Materials and New Energies, Shenzhen Technology University (SZTU) published a research article titled “Current-induced magnetization switching in a chemically disordered A1 CoPt single layer” in an applied physics letters journal Applied Physics Express (APEX) as co-first authors in February. The article was supervised by Associate Prof. An Hongyu from the College. Authorship is also shared by junior students Chen Zhiren and Zheng Hongnan and senior student Zeng Qi from the same college. The full text of this article can be found under https://doi.org/10.35848/1882-0786/abdcd5.

Associate Professor An Hong Yu, Chen Zehan and Liu Lin (from left to right) [Photo/College of New Materials and New Energies]

Current-induced magnetization switching through spin-orbit torques (SOTs) is essential for spin-orbitronic-based memory devices with low-energy consumption and high speed. Typically, in a heavy metal (HM)/ferromagnetic (FM) bilayer, SOTs can be generated through the bulk spin Hall effect in the HM layer and the Rashba effect at the HM/FM interface. When a charge current is applied, the generated SOTs transfer into the FM layer, and act as effective magnetic fields to manipulate the magnetization of the FM layer. Therefore, it has been considered that HMs or other SOT source materials are indispensable for generating SOTs and manipulating the magnetization of the FM layer. The article reports the first demonstration of current-induced magnetization switching in a perpendicularly magnetized A1 CoPt single layer. It shows that good perpendicular magnetic anisotropy can be obtained over a wide composition range of A1 Co_1−x Pt_x single layers, which allows the fabrication of a perpendicularly magnetized CoPt single layer with a composition gradient that breaks the inversion symmetry of the structure. By fabricating a CoPt single layer with a gradient, it was able to evaluate spin-orbit torque (SOT) efficiency and successfully realize SOT induced magnetization switching. The study provides an approach for realizing current-induced magnetization in ferromagnetic single layers without attaching SOT source materials.

Chen Zehan and Liu Lin are doing scientific research under the guidance of Associate Professor An Hongyu. [Photo/College of New Materials and New Energies]

Tips: (Some information below is cited from the official website of IOPscience.)

Applied Physics Express (APEX) is a letters journal devoted solely to rapid dissemination of up-to-date and concise reports on new findings in applied physics (2020 Journal Impact Factor: 3.086; JCR quartile: Q2). It is published by Institute of Physics (IOP) Publishing on behalf of the Japan Society of Applied Physics (JSAP). The motto of APEX is high scientific quality and prompt publication.

Drafted by Daisy（姚琦）/ International Cooperation & Student Affairs Office

Edited by International Cooperation & Student Affairs Office