Related papers: Impact of Ferroelectric Distortion on Thermopower …
Electrostriction is an important material property that characterizes how strain changes with the development of polarization inside a material. We show that \textit{ab initio }techniques developed in recent years can be exploited to…
In this paper we explore the different mechanisms that affect the thermopower of a band insulating perovskite (in this case, SrTiO$_3$) when subject to strain (both compressive or tensile). We analyze the high temperature, entropy dominated…
Modeling ferroelectric materials from first principles is one of the successes of density-functional theory, and the driver of much development effort, requiring an accurate description of the electronic processes and the thermodynamic…
We report modifications of the ferroelectric and electrocaloric properties of BaTiO$_3$ by defects. For this purpose, we have combined \textit{ab initio}-based molecular dynamics simulations with a simple model for defects. We find that…
The correlated couple of electrical and thermal property is the challenge to realize a substantial leap in thermoelectric materials.Synthesis of semiconductor and metal composites is a significant and versatile design strategy to optimize…
SrTiO$_3$ is an incipient ferroelectric on the verge of a polar instability, which is avoided at low temperatures by quantum fluctuations. Within this unusual quantum paraelectric phase, superconductivity persists despite extremely dilute…
We use first principles density functional theory calculations to investigate the effect of biaxial strain in the low-temperature structural and ferroelectric properties of [111]-oriented SrTiO$_3$. We find that [111] biaxial strain,…
We investigate basic properties of the thermopower (Seebeck coefficient) of phase-coherent conductors under the influence of dephasing and inelastic processes. Transport across the system is caused by a voltage bias or a thermal gradient…
In this paper we study the size effects of the ferroelectric nanotube phase diagrams and polar properties allowing for effective surface tension and depolarization field influence. The approximate analytical expression for the…
Bipolar carrier transport is often a limiting factor in the thermoelectric efficiency of narrow bandgap materials at high temperatures due to the reduction in the Seebeck coefficient and the introduction of an additional term to the thermal…
It has been proposed that paramagnetic materials exhibit a unique thermoelectric effect near the ferromagnetic transition point due to spin fluctuations. This phenomenon is often referred to as paramagnon drag. We calculate the contribution…
We have combined the Boltzmann transport equation with an {\it ab initio} approach to compute the thermoelectric coefficients of semiconductors. Electron-phonon, ionized impurity, and electron-plasmon scattering rates have been taken into…
Critical thermoelectric parameters including Seebeck coefficient, electrical conductivity, thermal conductivity and figure of merit ZT of one-dimensional coaxial Bi2Te3/Sb2Te3 nanocomposite were modeled by following the single carrier…
We explore the effect of charge carrier doping on ferroelectricity using density functional calculations and phenomenological modeling. By considering a prototypical ferroelectric material, BaTiO3, we demonstrate that ferroelectric…
Valley lines on total-energy surfaces for the zone-center distortions of free-standing and in-plane strained SrTiO3 are investigated with a newly developed first-principles structure optimization technique [Jpn. J. Appl. Phys. vol.43…
We study the origin of the large Seebeck coefficient despite the metallic conductivity in the La-doped SrTiO$_3$ and Ba-doped KTaO$_3$. We calculate the band structure of SrTiO$_3$ and KTaO$_3$, from which the Seebeck coefficient is…
Ferroelectrics with spontaneous electric polarization play an essential role in today's device engineering, such as capacitors and memories. Their physical properties are further enriched by suppressing the long-range polar order, as is…
We investigate the electrical conductivity and thermoelectric effects in topological crystalline insulators in the presence of short- and long-range impurity interactions. We employ the generalized Boltzmann formalism for anisotropic Fermi…
The Seebeck coefficient and electrical conductivity are two critical quantities to optimize simultaneously in designing thermoelectric materials, and they are determined by the dynamics of carrier scattering. We uncover a new regime where…
First-principles calculations were performed to investigate the ferroelectric properties of barium titanate and bismuth ferrite, as well as phonon dispersion of BaTiO3, using density functional theory and density functional perturbation…