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arXiv · 1102.0171

Unchanged thermopower enhancement at the semiconductor-metal transition in correlated FeSb$_{2-x}$Te$_x$

P. Sun·M. Søndergaard·Y. Sun·S. Johnsen·B. B. Iversen·F. Steglich
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Abstract

Substitution of Sb in FeSb$_2$ by less than 0.5% of Te induces a transition from a correlated semiconductor to an unconventional metal with large effective charge carrier mass $m^*$. Spanning the entire range of the semiconductor-metal crossover, we observed an almost constant enhancement of the measured thermopower compared to that estimated by the classical theory of electron diffusion. Using the latter for a quantitative description one has to employ an enhancement factor of 10-30. Our observations point to the importance of electron-electron correlations in the thermal transport of FeSb$_2$, and suggest a route to design thermoelectric materials for cryogenic applications.

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P. Sun, M. Søndergaard, Y. Sun, S. Johnsen, B. B. Iversen, F. Steglich. 2011-02-01. Unchanged thermopower enhancement at the semiconductor-metal transition in correlated FeSb$_{2-x}$Te$_x$. https://doi.org/10.1063/1.3556645

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