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arXiv · 2111.05417

Magnetotransport in ferromagnetic Fe$_2$Ge semimetallic thin films

Andrew W. Forbes·Niraj Bhattarai·Christopher Gassen·Raghad S. H. Saqat·Ian L. Pegg·John Philip
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Abstract

Thin films of the ferromagnet Fe$_2$Ge were grown via molecular beam epitaxy, and their electrical and magneto-transport properties measured for the first time. X-ray diffraction and vibrating sample magnetometry measurements confirmed the crystalline ferromagnetic Fe$_2$Ge phase. The observed high temperature maximum in the longitudinal resistivity, as well as the observed suppression of electron-magnon scattering at low temperatures, point to the presence of strong spin polarization in this material. Measurements of the Hall resistivity, $\rho_{xy}$, show contributions from both the ordinary Hall effect and anomalous Hall effect, $\rho_{xy}^{AH}$, from which we determined the charge carrier concentration and mobility. Measurements also show a small negative magnetoresistance in both the longitudinal and transverse geometries. Fe$_2$Ge holds promise as a useful spintronic material, especially for its semiconductor compatibility.

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Andrew W. Forbes, Niraj Bhattarai, Christopher Gassen, Raghad S. H. Saqat, Ian L. Pegg, John Philip. 2021-11-09. Magnetotransport in ferromagnetic Fe$_2$Ge semimetallic thin films. https://doi.org/10.1063/5.0079202

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