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arXiv · 2501.13542

Anisotropic suppression of the phononic thermal conductivity by magnetic field in SmAlSi

Mujeeb Ahmad·Md Shahin Alam·Xiaohan Yao·Fazel Tafti·Marcin Matusiak
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Abstract

We report the thermal and electrical conductivity data for the magnetic Weyl semimetal SmAlSi measured in a magnetic field (B) with two different orientations. In one case, B was applied perpendicular to the heat or charge current, in the other they were parallel. For both configurations, the magnetic field affects the magnetic structure identically as B is always parallel to the equivalent tetragonal axis. Our results indicate that phonon heat transport in response to the magnetic field exhibits strong anisotropy at low temperature: it appears to be independent of B in the perpendicular configuration but is strongly suppressed in the parallel configuration. Understanding this unusual behaviour can lead to designing better materials for thermoelectricity or directional heat switches.

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Mujeeb Ahmad, Md Shahin Alam, Xiaohan Yao, Fazel Tafti, Marcin Matusiak. 2025-01-23. Anisotropic suppression of the phononic thermal conductivity by magnetic field in SmAlSi. https://arxiv.org/abs/2501.13542

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