Ab Initio Studies of the Tunability of Topological Phases of Complex Materials

ORAL

Abstract

Recently, there have been intensive studies of new existing and hypothetical, as-yet-unsynthesized materials with topological phases. Using density functional theory-based approaches, we perform detailed calculations on several promising candidate compounds, including Bi- and Cd- based Dirac and Weyl semimetals and oxide topological insultaors, that are predicted to exhibit topological or near-topological states. We compute surface states of candidate materials such as Dirac semimetals Na3Bi and Cd3As2 along various surfaces. For systems with strong correlations, we examine the efficacy of DFT-based hybrid functionals and the GW approximation for accurate prediction of band inversion. For a selection of systems, we also explore quantitatively the tunability of topological phases via hydrostatic pressure, biaxial strain, broken crystal symmetry, or doping.

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Authors

  • Ru Chen

    University of California, Berkeley and Lawrence Berkeley National Lab

  • Ashvin Vishwanath

    University of California, Berkeley, UC Berkeley, University of California - Berkeley

  • Jeffrey Neaton

    Univ of California - Berkeley, Molecular Foundry, Lawrence Berkeley National Laboratory, Physics Department, UC Berkeley \& Molecular Foundry, LBNL \& Kavli Energy NanoSciences Institute at Berkeley, Berkeley, University of California at Berkeley, University of California, Berkeley; Lawrence Berkeley National Laboratory, Dept. of Physics, UC Berkeley, Molecular Foundry, Lawrence Berkeley National Laboratory; Department of Physics, University of California-Berkeley, University of California, Berkeley and Lawrence Berkeley National Lab, Molecular Foundry, Lawrence Berkeley National Laboratory, and Department of Physics, UC-Berkeley, Lawrence Berkeley National Laboratory