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arXiv · 2501.10485

Quantitative noncontact measurement of thermal Hall angle and transverse thermal conductivity by lock-in thermography

Takumi Imamura·Takamasa Hirai·Koichi Oyanagi·Ryo Iguchi·Kenta Takamori·Satoru Kobayashi·Ken-ichi Uchida
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Abstract

We propose and demonstrate a quantitative noncontact measurement method for the thermal Hall effect (THE) based on magnetic-field-modulated lock-in thermography. This method enables visualization of THE-induced temperature change and quantitative estimation of the thermal Hall angle $θ_{\rm THE}$ by applying periodic magnetic fields to a sample and obtaining the first harmonic response of thermal images. By combining this method with LIT-based measurement techniques for the longitudinal thermal conductivity $κ_{xx}$, we also quantify the transverse thermal conductivity $κ_{xy}$. We validate our measurement methods by estimating $θ_{\rm THE}$, $κ_{xx}$, and $κ_{xy}$ in a ferromagnetic Heusler alloy Co$_2$MnGa slab showing large THE.

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Takumi Imamura, Takamasa Hirai, Koichi Oyanagi, Ryo Iguchi, Kenta Takamori, Satoru Kobayashi, Ken-ichi Uchida. 2025-02-07. Quantitative noncontact measurement of thermal Hall angle and transverse thermal conductivity by lock-in thermography. https://doi.org/10.1103/physrevapplied.23.024018

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