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arXiv · 2308.11183

Tuning of Electrical, Magnetic, and Topological Properties of Magnetic Weyl Semimetal Mn$_{3+x}$Ge by Fe doping

Susanta Ghosh·Achintya Low·Soumya Ghorai·Kalyan Mandal·Setti Thirupathaiah
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Abstract

We report on the tuning of electrical, magnetic, and topological properties of the magnetic Weyl semimetal (Mn$_{3+x}$Ge) by Fe doping at the Mn site, Mn$_{(3+x)-\delta}$Fe$_{\delta}$Ge ($\delta$=0, 0.30, and 0.62). Fe doping significantly changes the electrical and magnetic properties of Mn$_{3+x}$Ge. The resistivity of the parent compound displays metallic behavior, the system with $\delta$=0.30 of Fe doping exhibits semiconducting or bad-metallic behavior, and the system with $\delta$=0.62 of Fe doping demonstrates a metal-insulator transition at around 100 K. Further, we observe that the Fe doping increases in-plane ferromagnetism, magnetocrystalline anisotropy, and induces a spin-glass state at low temperatures. Surprisingly, topological Hall state has been noticed at a Fe doping of $\delta$=0.30 that is not found in the parent compound or with $\delta$=0.62 of Fe doping. In addition, spontaneous anomalous Hall effect observed in the parent system is significantly reduced with increasing Fe doping concentration.

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Susanta Ghosh, Achintya Low, Soumya Ghorai, Kalyan Mandal, Setti Thirupathaiah. 2023-08-22. Tuning of Electrical, Magnetic, and Topological Properties of Magnetic Weyl Semimetal Mn$_{3+x}$Ge by Fe doping. https://doi.org/10.1088/1361-648x%2Facf262

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