Ultrafast Laser Control of Antiferromagnetic-Ferrimagnetic Switching in Two-Dimensional Ferromagnetic Semiconductor Heterostructures

Zhaobo Zhou; Zhenfa Zheng; Junjie He; Jinlan Wang; Oleg V Prezhdo; Thomas Frauenheim

doi:10.1021/acs.nanolett.3c01350

Ultrafast Laser Control of Antiferromagnetic-Ferrimagnetic Switching in Two-Dimensional Ferromagnetic Semiconductor Heterostructures

Nano Lett. 2023 Jun 28;23(12):5688-5695. doi: 10.1021/acs.nanolett.3c01350. Epub 2023 Jun 12.

Authors

Zhaobo Zhou¹, Zhenfa Zheng², Junjie He³, Jinlan Wang⁴, Oleg V Prezhdo⁵, Thomas Frauenheim^{6

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Affiliations

¹ Bremen Center for Computational Materials Science, University of Bremen, Bremen 28359, Germany.
² Department of Physics, University of Science and Technology of China, Hefei, Anhui 230026, China.
³ Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University in Prague, Prague 12843, Czech Republic.
⁴ School of Physics, Southeast University, Nanjing 211189, China.
⁵ Departments of Chemistry, and Physics and Astronomy, University of Southern California, Los Angeles, California 90089, United States.
⁶ School of Science, Constructor University, Bremen 28759, Germany.
⁷ Beijing Computational Science Research Center, Beijing 100193, China.
⁸ Shenzhen JL Computational Science and Applied Research Institute, Shenzhen 518109, China.

PMID: 37307217
DOI: 10.1021/acs.nanolett.3c01350

Abstract

Realizing ultrafast control of magnetization switching is of crucial importance for information processing and recording technology. Here, we explore the laser-induced spin electron excitation and relaxation dynamics processes of CrCl₃/CrBr₃ heterostructures with antiparallel (AP) and parallel (P) systems. Although an ultrafast demagnetization of CrCl₃ and CrBr₃ layers occurs in both AP and P systems, the overall magnetic order of the heterostructure remains unchanged due to the laser-induced equivalent interlayer spin electron excitation. More crucially, the interlayer magnetic order switches from antiferromagnetic (AFM) to ferrimagnetic (FiM) in the AP system once the laser pulse disappears. The microscopic mechanism underpinning this magnetization switching is dominated by the asymmetrical interlayer charge transfer combined with a spin-flip, which breaks the interlayer AFM symmetry and ultimately results in an inequivalent shift in the moment between two FM layers. Our study opens up a new idea for ultrafast laser control of magnetization switching in two-dimensional opto-spintronic devices.

Keywords: magnetization switching; nonadiabatic molecular dynamics; time-dependent density functional theory; two-dimensional ferromagnet; ultrafast spin dynamics.