Memory-function approach for electronic transport in disordered solids

ORAL

Abstract

We present an ab initio method for the evaluation of transport coefficients from electronic-structure calculations which goes beyond the relaxation-time approximation. We focus on the electrical conductivity that within the Kubo linear response theory is related to the current-current correlation function. We evaluate this correlation with a memory function approach including scattering processes to infinite order. We have implemented this method in the exciting code [1]. It only requires the non-interacting space- and time-dependent charge-charge correlation function and a description of the scattering mechanism. As a proof of principle, we calculate the conductivity of sodium limited by static disorder. The self-consistent approach describes the localization of the carriers in this simple metal for strong disorder. In comparison with the relaxation-time approximation, our method captures the Anderson localization of the system and corrects the overestimation of the conductivity in the metallic phase.

[1] Gulans et al., J. Phys.: Condens. Matter 26, 363202 (2014).

*M.T. acknowledges funding from the Elsa-Neumann Scholarship of Berlin.

–

Presenters

  • Maria Troppenz

    • Humboldt University of Berlin

Authors

  • Maria Troppenz

    • Humboldt University of Berlin

  • Brett Green

    • Pennsylvania State University

  • Santiago Rigamonti

    • Humboldt Universität zu Berlin, 12489 Berlin, DE
    • Humboldt University of Berlin

  • Claudia Draxl

    • Institut für Physik and IRIS Adlershof, Humboldt-Universität zu Berlin, Berlin, Germany
    • Humboldt Universität zu Berlin, 12489 Berlin, DE
    • Humboldt University of Berlin
    • Institut für Physik and IRIS Adlershof, Humboldt-Universität zu Berlin, 12489 Berlin, Germany
    • Physics Department and IRIS Adlershof, Humboldt University of Berlin

  • Jorge Osvaldo Sofo

    • Pennsylvania State University