Photon-Assisted Magnetization Reversal in van der Waals Ferromagnet Fe₃GeTe₂

CHUNG CHUN LU^1*, Wei-Qing Li¹, Jia-Xin Li¹, Ching Kuo¹, Kun-Hung Pan¹, Chang-Hua Liu¹

¹Institute of Photonics Technologies, National Tsing Hua University, Hsinchu, Taiwan

* Presenter:CHUNG CHUN LU, email:adgj2684@gapp.nthu.edu.tw

The rediscovery of van der Waals (vdW) magnetic materials has revitalized the study of intrinsic two dimensional (2D) magnetism and enabled exploration of unconventional means—such as electrostatic gating and strain engineering—to control magnetic states. However, photon-driven magnetization switching remains rarely observed in 2D magnets, despite its potential for ultrafast, high-density, and low-power spintronic applications. In this study, we employ Fe₃GeTe₂ (FGT), a vdW ferromagnet with strong perpendicular magnetic anisotropy, and observe that when the photon energy resonates with the electronic band structure, pulsed optical excitation effectively reduces the coercive field, enabling photo-assisted magnetization reversal. These findings demonstrate that FGT can serve as a promising platform for next-generation light-controlled spintronic memory, providing new opportunities for highspeed and energy-efficient data storage.

Keywords: Two-dimensional magnets, Photo-assisted magnetization reversal, Spintronics, Optical memory