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arXiv · 1505.02946

Unified picture for the colossal thermopower compound FeSb$_2$

M. Battiato·J. M. Tomczak·Z. Zhong·K. Held
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Abstract

We identify the driving mechanism of the gigantic Seebeck coefficient in FeSb$_2$ as the phonon-drag effect associated with an in-gap density of states that we demonstrate to derive from excess iron. We accurately model electronic and thermoelectric transport coefficients and explain the so far ill-understood correlation of maxima and inflection points in different response functions. Our scenario has far-reaching consequences for attempts to harvest the spectacular powerfactor of FeSb$_2$.

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M. Battiato, J. M. Tomczak, Z. Zhong, K. Held. 2015-05-12. Unified picture for the colossal thermopower compound FeSb$_2$. https://doi.org/10.1103/physrevlett.114.236603

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