First-order quantum phase transition in three-dimensional topological band insulators

ORAL

Abstract

It is commonly assumed that the transition between topologically distinct non-interacting gapped phases of fermions is necessarily accompanied by the closing of the gap as long as the symmetries of the Hamiltonian are maintained. We show that such a quantum phase transition is possible without closing the gap in the case of a three-dimensional topological band insulator [1]. We demonstrate this by calculating the free energy of the Bernevig-Hughes-Zhang model, and show that as the band curvature continuously varies, a jump between the band gap minima corresponding to the topologically trivial and nontrivial insulators occurs. Therefore, this first order phase transition is a generic feature of three-dimensional topological band-insulators. For a certain parameter range we predict a re-entrant topological phase transition. We discuss our findings in connection with the recent experimental observation of a discontinuous phase transition in a family of topological crystalline insulators. [1] V. Juricic, D. S. L. Abergel, and A. V. Balatsky, arXiv: 1608.07819.

–

Authors

  • Vladimir Juricic

    • Nordita, Center for Quantum Materials, Stockholm University and KTH, Stockholm

  • David Abergel

    • Nordita
    • Nordita, Center for Quantum Materials, Stockholm University and KTH, Stockholm

  • Alexander Balatsky

    • Nordita, KTH Royal Institute of Technology, Stockholm University and Los Alamos National Laboratory
    • Nordita, KTH Royal Institute of Technology and Stockholm University; Institute for Materials Science, Los Alamos National Laboratory, USA
    • Nordita, Center for Quantum Materials, KTH Royal Institute of Technology and Stockholm University, Stockholm, Sweden
    • Nordita, KTH Royal Institute of Technology and Stockholm University; Institute for Materials Science, Los Alamos National Laboratory
    • Los Alamos National Laboratory, NORDITA
    • Institute for Materials Science, Los Alamos National Laboratory, USA; Nordita, KTH Royal Institute of Technology and Stockholm University, Sweden
    • Nordita, Center for Quantum Materials, KTH Royal Institute of Technology and Stockholm University, Roslagstullsbacken 23, SE-106 91 Stockholm, Sweden
    • Nordita, Center for Quantum Materials, Stockholm University and KTH, Stockholm and Institute for Materials Science, LANL, Los Alamos, USA