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arXiv · 2404.11414

Anisotropic Nonsaturating Magnetoresistance Observed in HoMn$_6$Ge$_6$: A Kagome Dirac Semimetal

Achintya Low·Tushar Kanti Bhowmik·Susanta Ghosh·Setti Thirupathaiah
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Abstract

We report the magnetic and magnetotransport properties and electronic band structure of the kagome Dirac semimetal HoMn$_6$Ge$_6$. Temperature-dependent electrical resistivity demonstrates various magnetic-transition-driven anomalies. Notably, a crossover from negative to positive magnetoresistance (MR) is observed at around 150 K. While the linear nonsaturating positive MR in the low-temperature region is mainly driven by the linear Dirac-like band dispersions as predicted by the first-principles calculations, the negative MR observed in the high-temperature region is due to the spin-flop type magnetic transition. Consistent with anisotropic Fermi surface topology, we observe anisotropic magnetoresistance at low temperatures. A significant anomalous Hall effect has been noticed at high temperatures in addition to a switching of the dominant charge carrier from electron to hole at around 215 K.

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Achintya Low, Tushar Kanti Bhowmik, Susanta Ghosh, Setti Thirupathaiah. 2024-04-17. Anisotropic Nonsaturating Magnetoresistance Observed in HoMn$_6$Ge$_6$: A Kagome Dirac Semimetal. https://arxiv.org/abs/2404.11414

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