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arXiv · 2306.00081

Pressure evolution of electronic structure and magnetism in the layered van der Waals ferromagnet CrGeTe$_3$

Han-Xiang Xu·Makoto Shimizu·Daniel Guterding·Junya Otsuki·Harald O. Jeschke
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Abstract

Layered van der Waals ferromagnets, which preserve their magnetic properties down to exfoliated monolayers, are fueling an abundance of fundamental research and nanoscale device demonstration. CrGeTe$_3$ is a prime example for this class of materials. Its temperature-pressure phase diagram features an insulator-to-metal transition and a significant increase of ferromagnetic Curie-Weiss temperatures upon entering the metallic state. We use density functional theory to understand the magnetic exchange interactions in CrGeTe$_3$ at ambient and elevated pressure. We calculate Heisenberg exchange couplings, which provide the correct ferromagnetic ground state and explain the experimentally observed pressure dependence of magnetism in CrGeTe$_3$. Furthermore, we combine density functional theory with dynamical mean field theory to investigate the effects of electronic correlations and the nature of the high pressure metallic state in CrGeTe$_3$.

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Han-Xiang Xu, Makoto Shimizu, Daniel Guterding, Junya Otsuki, Harald O. Jeschke. 2023-05-31. Pressure evolution of electronic structure and magnetism in the layered van der Waals ferromagnet CrGeTe$_3$. https://doi.org/10.1103/physrevb.108.125142

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