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arXiv · 2105.08228

Theory of thermopolarization effect

Yugo Onishi·Hiroki Isobe·Atsuo Shitade·Naoto Nagaosa
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Abstract

We study the polarization response to the temperature gradient in insulators, known as the thermopolarization effect. We show that this response can be understood through the free energy response function to an electric field gradient, which we call Q-tensor. By using the Q-tensor, we present a unified description of the polarization responses to both electric fields and temperature gradients and derive the generalized Mott relation. Additionally, we draw an analogy with the anomalous Hall and Nernst effects. These effects are observable as the Seebeck effect where the linear size of the system is shorter than the screening length.

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Yugo Onishi, Hiroki Isobe, Atsuo Shitade, Naoto Nagaosa. 2021-05-18. Theory of thermopolarization effect. https://doi.org/10.1021/acs.nanolett.4c05870

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