English

Tailoring coercive fields and the Curie temperature via proximity coupling in WSe$_2$/Fe$_3$GeTe$_2$ van der Waals heterostructures

Mesoscale and Nanoscale Physics 2024-04-30 v1

Abstract

Hybrid structures consisting of two-dimensional (2D) magnets and semiconductors have exhibited extensive functionalities in spintronics and opto-spintronics. In this work, we have fabricated WSe2_2/Fe3_3GeTe2_2 van der Waals (vdW) heterostructures and investigated the proximity effects on 2D magnetism. Through reflective magnetic circular dichroism (RMCD), we have observed a temperature-dependent modulation of magnetic order in the heterostructure. For temperatures above 4040 K, WSe2_2-covered Fe3_3GeTe2_2 exhibits a larger coercive field than that observed in bare Fe3_3GeTe2_2, accompanied by a noticeable enhancement of the Curie temperature by 2121 K. This strengthening suggests an increase in magnetic anisotropy in the interfacial Fe3_3GeTe2_2 layer, which can be attributed to the spin-orbit coupling (SOC) proximity effect induced by the adjacent WSe2_2 layers. However, at much lower temperatures (T<20T<20 K), a non-monotonic modification of the coercive field is observed, showing both reduction and enhancement, which depends on the thickness of the WSe2_2 and Fe3_3GeTe2_2 layers. Moreover, an unconventional two-step magnetization process emerges in the heterostructure, indicating the short-range nature of SOC proximity effects. Our findings revealing proximity effects on 2D magnetism may shed light on the design of future spintronic and memory devices based on 2D magnetic heterostructures.

Keywords

Cite

@article{arxiv.2404.18146,
  title  = {Tailoring coercive fields and the Curie temperature via proximity coupling in WSe$_2$/Fe$_3$GeTe$_2$ van der Waals heterostructures},
  author = {Guodong Ma and Renjun Du and Fuzhuo Lian and Song Bao and Zijing Guo and Xiaofan Cai and Jingkuan Xiao and Yaqing Han and Di Zhang and Siqi Jiang and Jiabei Huang and Xinglong Wu and Alexander S. Mayorov and Jinsheng Wen and Lei Wang and Geliang Yu},
  journal= {arXiv preprint arXiv:2404.18146},
  year   = {2024}
}