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arXiv · 1804.06392

Anomalous Hall effect in van der Waals bonded ferromagnet Fe$_{3-x}$GeTe$_2$

Yu Liu·Eli Stavitski·Klaus Attenkofer·C. Petrovic
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Abstract

We report anomalous Hall effect (AHE) in single crystals of quasi-two-dimensional Fe$_{3-x}$GeTe$_2$ ($x \approx 0.36$) ferromagnet grown by the flux method which induces defects on Fe site and bad metallic resistivity. Fe K-edge x-ray absorption spectroscopy was measured to provide information on local atomic environment in such crystals. The dc and ac magnetic susceptibility measurements indicate a second-stage transition below 119 K in addition to the paramagnetic to ferromagnetic transition at 153 K. A linear scaling behavior between the modified anomalous Hall resistivity $ρ_{xy}/μ_0H_{eff}$ and longitudinal resistivity $ρ_{xx}^2M/μ_0H_{eff}$ implies that the AHE in Fe$_{3-x}$GeTe$_2$ should be dominated by the intrinsic Karplus-Luttinger mechanism rather than the extrinsic skew-scattering and side-jump mechanisms. The observed deviation in the linear-M Hall conductivity $σ_{xy}^A$ below 30 K is in line with its transport characteristic at low temperatures, implying the scattering of conduction electrons due to magnetic disorder and the evolution of the Fermi surface induced by possible spin-reorientation transition.

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Yu Liu, Eli Stavitski, Klaus Attenkofer, C. Petrovic. 2018-04-17. Anomalous Hall effect in van der Waals bonded ferromagnet Fe$_{3-x}$GeTe$_2$. https://doi.org/10.1103/physrevb.97.165415

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