First-Principles Studies of TiAsRh, a new Dirac nodal line system

ORAL

Abstract

A recent development in condensed matter physics is the discovery of topological semimetals which have features in the band structure protected by an interplay of symmetry and topology. Dirac Nodal Line (DNL) systems are one such class of materials in which the conduction and valence bands touch in a closed loop in momentum space. Using density functional theory (DFT) calculations, we propose that TiAsRh is a DNL system and study the symmetry leading to the DNL. We find that a mirror plane protects the crossings without spin-orbit coupling (SOC), and demonstrate that SOC modestly gaps out the NL. We perform our study with standard semi-local and hybrid density functionals and show that the nodal line is robust with respect to functional. Implications for experiments on this compound, which has been previously synthesized, are discussed.

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Authors

  • Sophie Weber

    Department of Physics, UC Berkeley

  • Ru Chen

    Lawrence Berkeley National Laboratory, Department of Physics, UC Berkeley; Molecular Foundry, LBNL, Lawrence Berkeley National Lab; University of California, Berkeley

  • Qimin Yan

    Temple University, Lawrence Berkeley National Laboratory, Temple University, Department of Physics, UC Berkeley; Molecular Foundry, LBNL; Department of Physics, Temple University

  • Jeffrey B. Neaton

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