Proximity Effect-Induced Magnetoresistance Enhancement in a Fe3GeTe2/NbSe2/Fe3GeTe2 Magnetic Tunnel Junction

Xiangyu Zeng; Ge Ye; Fazhi Yang; Qikai Ye; Liang Zhang; Boyang Ma; Yulu Liu; Mengwei Xie; Genquan Han; Yue Hao; Jikui Luo; Xin Lu; Yan Liu; Xiaozhi Wang

doi:10.1021/acsami.3c15363

Proximity Effect-Induced Magnetoresistance Enhancement in a Fe₃GeTe₂/NbSe₂/Fe₃GeTe₂ Magnetic Tunnel Junction

ACS Appl Mater Interfaces. 2023 Dec 5. doi: 10.1021/acsami.3c15363. Online ahead of print.

Authors

Xiangyu Zeng^{1

2}, Ge Ye³, Fazhi Yang⁴, Qikai Ye⁵, Liang Zhang⁶, Boyang Ma⁵, Yulu Liu⁵, Mengwei Xie³, Genquan Han^{1

2}, Yue Hao^{1

2}, Jikui Luo⁵, Xin Lu³, Yan Liu^{1

2}, Xiaozhi Wang⁵

Affiliations

¹ Hangzhou Institute of Technology, Xidian University, Hangzhou 311200, China.
² State Key Discipline Laboratory of Wide Band Gap Semiconductor Technology, School of Microelectronics, Xidian University, Xi'an 710071, China.
³ Center for Correlated Matter and Department of Physics, Zhejiang University, Hangzhou 310027, China.
⁴ Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
⁵ College of Information Science and Electronic Engineering, Zhejiang University, Hangzhou 310027, China.
⁶ Research Center for Humanoid Sensing and Perception, Zhejiang Lab, Hangzhou 311100, China.

PMID: 38050752
DOI: 10.1021/acsami.3c15363

Abstract

The coupling between van der Waals-layered magnetic and superconducting materials holds the possibility of revealing novel physical mechanisms and realizing spintronic devices with new functionalities. Here, we report on the realization and investigation of a maximum ∼17-fold magnetoresistance (MR) enhancement based on a vertical magnetic tunnel junction of Fe₃GeTe₂ (FGT)/NbSe₂/FGT near the NbSe₂ layer's superconducting critical temperature (T_C) of 6.8 K. This enhancement is attributed to the band splitting in the atomically thin NbSe₂ spacer layer induced by the magnetic proximity effect on the material interfaces. However, the band splitting is strongly suppressed by the interlayer coupling in the thick NbSe₂ layer. Correspondingly, the device with a thick NbSe₂ layer displays no MR increase near T_C but a current dependent on transport properties at extremely low temperatures. This work carefully investigates the mechanism of MR enhancement, paving an efficient way for the modulation of spintronics' properties and the achievement of spin-based integrated circuits.

Keywords: magnetic proximity effect; magnetic tunnel junction; magnetoresistance enhancement; van der Waals heterojunction.