Dependence of electrical transport properties of CaO(CaMnO3)(m) (m=1, 2, 3, infinity) thermoelectric oxides on lattice periodicity

作者：Baranovskiy Andrei; Amouyal Yaron^*

来源：Journal of Applied Physics, 2017, 121(6): 065103.

DOI：10.1063/1.4975471

The electrical transport properties of CaO(CaMnO3)(m) (m = 1, 2, 3, infinity) compounds are studied applying the density functional theory (DFT) in terms of band structure at the vicinity of the Fermi level (E-F). It is shown that the total density of states (DOS) values at E-F increase with increase in the m-values, which implies an increase in the electrical conductivity, sigma, with increasing m-values, in full accordance with experimental results. Additionally, the calculated values of the relative slopes of the DOS at E-F correlate with the experimentally measured Seebeck coefficients. The electrical conductivity and Seebeck coefficients were calculated in the framework of the Boltzmann transport theory applying the constant relaxation time approximation. By the analysis of experimental and calculated sigma(T) dependences, the electronic relaxation time and mean free path values were estimated. It is shown that the electrical transport is dominated by electron scattering on the boundaries between perovskite (CaMnO3) and Ca oxide (CaO) layers inside the crystal lattice. Published by AIP Publishing.

• 出版日期2017-2-14