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arXiv · 2303.11596

Large and tunable magnetoresistance in van der Waals Ferromagnet/Semiconductor junctions

Wenkai Zhu·Yingmei Zhu·Tong Zhou·Xianpeng Zhang·Hailong Lin·Qirui Cui·Faguang Yan·Ziao Wang·Yongcheng Deng·Hongxin Yang·Lixia Zhao·Igor Žutić·Kirill D. Belashchenko·Kaiyou Wang
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Abstract

Magnetic tunnel junctions (MTJs) with conventional bulk ferromagnets separated by a nonmagnetic insulating layer are key building blocks in spintronics for magnetic sensors and memory. A radically different approach of using atomically-thin van der Waals (vdW) materials in MTJs is expected to boost their figure of merit, the tunneling magnetoresistance (TMR), while relaxing the lattice-matching requirements from the epitaxial growth and supporting high-quality integration of dissimilar materials with atomically-sharp interfaces. We report TMR up to 192% at 10 K in all-vdW Fe3GeTe2/GaSe/Fe3GeTe2 MTJs. Remarkably, instead of the usual insulating spacer, this large TMR is realized with a vdW semiconductor GaSe. Integration of two-dimensional ferromagnets in semiconductor-based vdW junctions offers gate-tunability, bias dependence, magnetic proximity effects, and spin-dependent optical-selection rules. We demonstrate that not just the magnitude, but also the TMR sign is tuned by the applied bias or the semiconductor thickness, enabling modulation of highly spin-polarized carriers in vdW semiconductors.

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Wenkai Zhu, Yingmei Zhu, Tong Zhou, Xianpeng Zhang, Hailong Lin, Qirui Cui, Faguang Yan, Ziao Wang, Yongcheng Deng, Hongxin Yang, Lixia Zhao, Igor Žutić, Kirill D. Belashchenko, Kaiyou Wang. 2023-03-21. Large and tunable magnetoresistance in van der Waals Ferromagnet/Semiconductor junctions. https://doi.org/10.1038/s41467-023-41077-0

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