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arXiv · 1502.03525

Impact of Ferroelectric Distortion on Thermopower in BaTiO3

Hiroaki Saijo·Kunihiko Yamauchi·Koun Shirai·Tamio Oguchi
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Abstract

We present a strategy for increasing thermoelectric performance by invoking ferroelectric distortion in a transition-metal oxide. By using an ab initio calculation approach with the Boltzmann transport equation, a large Seebeck coefficient is calculated in n-type BaTiO3. The polar structural distortion causes the peculiar dispersion of the lowest conduction band, which enhances the Seebeck coefficient along the polar direction. A microscopic mechanism of carrier concentration dependence of the Seebeck coefficient is discussed in terms of the band velocity distribution in the Brillouin zone.

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Hiroaki Saijo, Kunihiko Yamauchi, Koun Shirai, Tamio Oguchi. 2015-02-12. Impact of Ferroelectric Distortion on Thermopower in BaTiO3. https://doi.org/10.7566/jpsj.84.054701

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