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arXiv · 2204.02764

Thermoelectric Effect in Mott Variable-Range Hopping

Takahiro Yamamoto·Masao Ogata·Hidetoshi Fukuyama
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Abstract

On the basis of the Kubo-Luttinger linear response theory combined with the scaling theory of Anderson localization predicting the energy dependence of localization length near the mobility edge, we have studied the thermoelectric response of a disordered system exhibiting Mott variable-range hopping (VRH). We found that the low-tempetature Seebeck coefficient for VRH conduction in a $d$-dimensional system varies as $S\propto T^{d/(d+1)}$, which is different from the widely used expression, $S\propto T^{(d-1)/(d+1)}$, based on the energy-independent localization length. It is seen that the low-$T$ behavior of $S(T)$ of the thiospinel CuCrTiS$_4$ is in full agreement with the new scheme.

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Takahiro Yamamoto, Masao Ogata, Hidetoshi Fukuyama. 2022-04-06. Thermoelectric Effect in Mott Variable-Range Hopping. https://doi.org/10.7566/jpsj.91.044704

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