We demonstrate single shot al optical switching (AOS) in rare earth free CoFeB/MgO magnetic tunnel junctions (MTJs), a material system widely adopted in spin transfer torque magnetic random access memory (STT MRAM). By tuning the capping layer thickness, we show that precise heat control enables deterministic magnetization reversal from parallel (P) to antiparallel (AP) state. Furthermore, we detect magnetization reversal in a micro scale MTJ device via the tunnel magnetoresistance (TMR) effect. Our findings suggest that ultrafast spin transport or dipolar interactions or a combination of both may play essential roles in the switching process. This work represents a significant step toward integrating AOS with MTJ technology.
@article{arxiv.2510.25102,
title = {Single-Shot All-Optical Switching in CoFeB/MgO Magnetic Tunnel Junctions},
author = {Junta Igarashi and Sébastien Geiskopf and Takanobu Shinoda and Butsurin Jinnai and Yann Le Guen and Julius Hohlfeld and Shunsuke Fukami and Hideo Ohno and Jon Gorchon and Stéphane Mangin and Michel Hehn and Grégory Malinowski},
journal= {arXiv preprint arXiv:2510.25102},
year = {2025}
}