R&D: Phase-Change Control of Anomalous Hall Effect in Ferromagnetic MnBi Thin Films

Applied Physics Letters has published an article written by Siyue Zhang, Department of Basic Science, The University of Tokyo, Komaba, Meguro 153-8902, Japan, Yu Miyazaki, Department of Applied Physics, The University of Tokyo, Hongo, Bunkyo 113-8656, Japan, Tomoyuki Yokouchi, and Yuki Shiomi, Department of Basic Science, The University of Tokyo, Komaba, Meguro 153-8902, Japan.

Abstract: “We have experimentally demonstrated a phase change control of Hall effects in ferromagnetic MnBi thin films at room temperature. Two distinct ferromagnetic phases, i.e., a low-temperature phase and a quenched high-temperature phase, were obtained by slow-cooling or quenching the sputtered MnBi films. The measurement of Hall effects showed that the anomalous Hall resistivity has different coercivity and remanence between the two phases. By optimizing the Mn/Bi ratio, it is even possible to repeatedly switch the sign of Hall resistivity, which could be utilized as a concept of phase-change memory based on ferromagnetic transport.“

This work was supported by the JST FOREST Program, Grant No. JPMJFR203H; by JSPS KAKENHI, Grant Nos. JP21H01794, JP22H05449, JP22H04464, JP21K18890, and JP19H05600; and by the Murata Science Foundation.