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Title: Spin filtering effect in intrinsic 2D magnetic semiconductor Cr 2 Ge 2 Te 6
All van der Waals Fe 3 GeTe 2 /Cr 2 Ge 2 Te 6 /graphite magnetic heterojunctions have been fabricated via mechanical exfoliation and stacking, and their magnetotransport properties are studied in detail. At low bias voltages, large negative junction magnetoresistances have been observed and are attributed to spin-conserving tunneling transport across an insulating Cr 2 Ge 2 Te 6 layer. With increasing bias, a crossover to Fowler–Nordheim tunneling takes place. The negative sign of the tunneling magnetoresistance suggests that the bottom of a conduction band in Cr 2 Ge 2 Te 6 belongs to minority spins, opposite to the findings of some first-principles calculations. This work shows that the vdW heterostructures based on 2D magnetic insulators are a valuable platform to gain further insight into spin polarized tunneling transport, which is the basis for pursuing high performance spintronic devices and a large variety of quantum phenomena.  more » « less
Award ID(s):
1905843
NSF-PAR ID:
10418311
Author(s) / Creator(s):
; ; ; ; ; ; ;
Date Published:
Journal Name:
Applied Physics Letters
Volume:
121
Issue:
14
ISSN:
0003-6951
Page Range / eLocation ID:
142402
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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