Impact of Ferroelectric Distortion on Thermopower in BaTiO3

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.

6 pages, 6 figures, submitted to JPSJ

References in corpus (4)

• "Pudding mold" band drives large thermopower in Na${}_x$CoO${}_2$
• Ferroelectric Instability under Screened Coulomb Interactions
• Effect of the surface polarization in polar perovskites studied from first principles
• Origin of coexisting large Seebeck coefficient and metallic conductivity in the electron doped SrTiO${}_3$ and KTaO${}_3$