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DOE OSTI · 1661231

Interlayer magnetism in Fe 3-x GeTe 2

Kong, Xiangru·Nguyen, Giang D.·Lee, Jinhwan·Lee, Changgu·Calder, Stuart·May, Andrew F.·Gai, Zheng·Li, An-Ping·Liang, Liangbo·Berlijn, Tom
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Abstract

Fe 3 - x GeTe 2 is a layered van der Waals magnetic material with a relatively high ordering temperature and large anisotropy. While most studies have concluded the interlayer ordering to be ferromagnetic, there have also been reports of interlayer antiferromagnetism in Fe 3 - x GeTe 2 . In this work, we investigate the interlayer magnetic ordering by neutron diffraction experiments, scanning tunneling microscopy (STM) and spin-polarized STM measurements, density functional theory plus U calculations, and STM simulations. We conclude that the layers of Fe 3 - x GeTe 2 are coupled ferromagnetically and that in order to capture the magnetic and electronic properties of Fe 3 - x GeTe 2 within density functional theory, Hubbard U corrections need to be taken into account.

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2-dimensional systems71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICSMagnetism

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Kong, Xiangru, Nguyen, Giang D., Lee, Jinhwan, Lee, Changgu, Calder, Stuart, May, Andrew F., Gai, Zheng, Li, An-Ping, Liang, Liangbo, Berlijn, Tom. 2020-09-09. Interlayer magnetism in Fe 3-x GeTe 2. https://doi.org/10.1103/physrevmaterials.4.094403

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