Ultrafast Laser Modulation of Local Magnetization Orientation in Perpendicularly Exchange-Coupled Bilayer

Frontiers in Physics

Wei Zhang¹  Zhifeng Chen¹  Jipei Chen¹  Jielin Zhou²  Zhikun Xie²  Yuanhai Cai²  Jun Peng² 

[1] Research Center for Advanced Information Materials (CAIM), Guangzhou University, Guangzhou, China;School of Physics and Materials Science, Guangzhou University, Guangzhou, China;

关键词: magnetization dynamics;    exchange coupling;    time-resolved magneto-optical Kerr spectroscopy;    magnetization reorientation;    femtosecond laser;    micromagnetic simulation;   

DOI  :  10.3389/fphy.2021.755081

来源: DOAJ

【 摘 要 】

Laser-induced magnetization dynamics in a perpendicularly exchange-coupled TbFeCo/GdFeCo bilayer film are studied by using pump-probe magneto-optical Kerr spectroscopy. An ultrafast modulation effect on local magnetization orientation is observed. Such ultrafast magnetization reorientation in the GdFeCo layer is revealed to be triggered by the femtosecond laser pulse and driven by the effective exchange field. These processes occur within a timescale of hundreds of picoseconds, in which the field- and fluence-dependent dynamical behaviors are demonstrated. In addition, an atomistic Heisenberg model is proposed for studying the laser-induced magnetization dynamics by using micromagnetic simulation. The simulated results agree with the experimental phenomena and further reveal the underlying mechanism. These results show an approach for ultrafast manipulation of the local magnetization orientation in perpendicularly exchange-coupled structures.

【 授权许可】

Unknown