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Title: Accessing new magnetic regimes by tuning the ligand spin-orbit coupling in van der Waals magnets
Van der Waals (VdW) materials have opened new directions in the study of low dimensional magnetism. A largely unexplored arena is the intrinsic tuning of VdW magnets toward new ground states. Chromium trihalides provided the first such example with a change of interlayer magnetic coupling emerging upon exfoliation. Here, we take a different approach to engineer previously unknown ground states, not by exfoliation, but by tuning the spin-orbit coupling (SOC) of the nonmagnetic ligand atoms (Cl, Br, I). We synthesize a three-halide series, CrCl 3 − x − y Br x I y , and map their magnetic properties as a function of Cl, Br, and I content. The resulting triangular phase diagrams unveil a frustrated regime near CrCl 3 . First-principles calculations confirm that the frustration is driven by a competition between the chromium and halide SOCs. Furthermore, we reveal a field-induced change of interlayer coupling in the bulk of CrCl 3 − x − y Br x I y crystals at the same field as in the exfoliation experiments.  more » « less
Award ID(s):
1700030 1708929 1712128
PAR ID:
10175673
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Science Advances
Volume:
6
Issue:
30
ISSN:
2375-2548
Page Range / eLocation ID:
eabb9379
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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