Effective mass and Fermi surface complexity factor from ab initio band structure calculations

Effective mass and Fermi surface complexity factor from ab initio band structure calculations

TitleEffective mass and Fermi surface complexity factor from ab initio band structure calculations
Publication TypeJournal Article
Year of Publication2017
AuthorsZachary M Gibbs, Francesco Ricci, Guodong Li, Hong Zhu, Kristin A Persson, Gerbrand Ceder, Geoffroy Hautier, Anubhav Jain, G. Jeffrey Snyder
Journalnpj Computational Materials
Volume3
Issue1
Date Published02/2017
Abstract

The effective mass is a convenient descriptor of the electronic band structure used to characterize the density of states and electron transport based on a free electron model. While effective mass is an excellent first-order descriptor in real systems, the exact value can have several definitions, each of which describe a different aspect of electron transport. Here we use Boltzmann transport calculations applied to ab initio band structures to extract a density-of-states effective mass from the Seebeck Coefficient and an inertial mass from the electrical conductivity to characterize the band structure irrespective of the exact scattering mechanism. We identify a Fermi Surface Complexity Factor: N* vK* from the ratio of these two masses, which in simple cases depends on the number of Fermi surface pockets ðN* vÞ and their anisotropy K* , both of which are beneficial to high thermoelectric performance as exemplified by the high values found in PbTe. The Fermi Surface Complexity factor can be used in high-throughput search of promising thermoelectric materials

DOI10.1038/s41524-017-0013-3
Short Titlenpj Comput Mater
Refereed DesignationRefereed