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Updated: Apr 29, 2026
Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Phonons regulate covalency: a new way to modulate the magnetism and Curie temperature of CrI3
Ke Wang1, Shuxin Yang1, Kai Ren2
1School of Automation, Xi'an University of Posts and Telecommunications, Shaanxi 710121, China. kewang@xupt.edu.cn.
Abstract:
Recently, diverse strategies have been exploited to engineer the magnetism of two-dimensional (2D) magnets to widen their application in spintronics. Here, we demonstrate the effect of manipulating optical phonons on the magnetism and Curie temperature (TC) of ferromagnetic CrI3. The first-principles calculations reveal that the anisotropy governed by dipole-dipole coupling exhibits negligible variations under 14 optical phonons, while the E4g (∼18.65%) and A11g (∼8.75%) modes can increase the magneto-crystalline anisotropic parameter (Kij) remarkably. Based on mean-field theory, we theoretically predict the Curie temperature of a CrI3 monolayer both in the absence and presence of phonon vibrations. Intriguingly, despite the E4g and A11g modes increasing Kij, they decrease TC by 3.76% and 16.10%, respectively. Conversely, the E3u and A22g modes enhance TC by 6.63% and 4.77%. The underlying mechanism is that E4g and A11g weaken the covalency and super-exchange coupling between Cr and I atoms, whereas the E3u and A22g modes strengthen them. Our work offers valuable theoretical insights for the application of 2D magnetic materials in spintronics.
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