Accurate ab initio tight-binding Hamiltonians: Effective tools for electronic transport and optical spectroscopy from first principles

Published

Journal Article

© 2016 American Physical Society. The calculations of electronic transport coefficients and optical properties require a very dense interpolation of the electronic band structure in reciprocal space that is computationally expensive and may have issues with band crossing and degeneracies. Capitalizing on a recently developed pseudoatomic orbital projection technique, we exploit the exact tight-binding representation of the first-principles electronic structure for the purposes of (i) providing an efficient strategy to explore the full band structure En(k), (ii) computing the momentum operator differentiating directly the Hamiltonian, and (iii) calculating the imaginary part of the dielectric function. This enables us to determine the Boltzmann transport coefficients and the optical properties within the independent particle approximation. In addition, the local nature of the tight-binding representation facilitates the calculation of the ballistic transport within the Landauer theory for systems with hundreds of atoms. In order to validate our approach we study the multivalley band structure of CoSb3 and a large core-shell nanowire using the ACBN0 functional. In CoSb3 we point the many band minima contributing to the electronic transport that enhance the thermoelectric properties; for the core-shell nanowire we identify possible mechanisms for photo-current generation and justify the presence of protected transport channels in the wire.

Full Text

Duke Authors

Cited Authors

  • D'Amico, P; Agapito, L; Catellani, A; Ruini, A; Curtarolo, S; Fornari, M; Nardelli, MB; Calzolari, A

Published Date

  • October 26, 2016

Published In

Volume / Issue

  • 94 / 16

Electronic International Standard Serial Number (EISSN)

  • 2469-9969

International Standard Serial Number (ISSN)

  • 2469-9950

Digital Object Identifier (DOI)

  • 10.1103/PhysRevB.94.165166

Citation Source

  • Scopus