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  • Electronic structure and magnetic exchange interactions of Cr-based van der Waals ferromagnets. A comparative study between CrBr 3 and Cr 2 Ge 2 Te 6
Title: Electronic structure and magnetic exchange interactions of Cr-based van der Waals ferromagnets. A comparative study between CrBr 3 and Cr 2 Ge 2 Te 6
Low dimensional magnetism has been powerfully boosted as a promising candidate for numerous applications. The stability of the long-range magnetic order is directly dependent on the electronic structure and the relative strength of the competing magnetic exchange constants. Here, we report a comparative pressure-dependent theoretical and experimental study of the electronic structure and exchange interactions of two-dimensional ferromagnets CrBr 3 and Cr 2 Ge 2 Te 6 . While CrBr 3 is found to be a Mott–Hubbard-like insulator, Cr 2 Ge 2 Te 6 shows a charge-transfer character due to the broader character of the Te 5p bands at the Fermi level. This different electronic behaviour is responsible for the robust insulating state of CrBr 3 , in which the magnetic exchange constants evolve monotonically with pressure, and the proximity to a metal–insulator transition predicted for Cr 2 Ge 2 Te 6 , which causes a non-monotonic evolution of its magnetic ordering temperature. We provide a microscopic understanding for the pressure evolution of the magnetic properties of the two systems.  more » « less
Award ID(s):
1729588 1949701 1720595
PAR ID:
10284580
Author(s) / Creator(s):
; ; ; ; ; ; ;
Date Published:
Journal Name:
Journal of Materials Chemistry C
Volume:
8
Issue:
39
ISSN:
2050-7526
Page Range / eLocation ID:
13582 to 13589
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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