Topology of Disconnected Elementary Band Representations

Cano J, Bradlyn B, Wang Z, Elcoro L, Vergniory MG, Felser C, Aroyo M, Bernevig BA (2018)

Publication Type: Journal article

Publication year: 2018

Journal

Physical Review Letters American Physical Society

Book Volume: 120

Article Number: 266401

Journal Issue: 26

DOI: 10.1103/PhysRevLett.120.266401

Abstract

Elementary band representations are the fundamental building blocks of atomic limit band structures. They have the defining property that at partial filling they cannot be both gapped and trivial. Here, we give two examples - one each in a symmorphic and a nonsymmorphic space group - of elementary band representations realized with an energy gap. In doing so, we explicitly construct a counterexample to a claim by Michel and Zak that single-valued elementary band representations in nonsymmorphic space groups with time-reversal symmetry are connected. For each example, we construct a topological invariant to explicitly demonstrate that the valence bands are nontrivial. We discover a new topological invariant: a movable but unremovable Dirac cone in the "Wilson Hamiltonian" and a bent-Z2 index.

Involved external institutions

Princeton University US United States (USA) (US) University of Basque Country / Universidad del Pais Vasco (UPV) / Euskal Herriko Unibersitatea (EHU) ES Spain (ES) Donostia International Physics Center (DIPC) ES Spain (ES) Max-Planck-Institut für Chemische Physik fester Stoffe (MPI CPfS) / Max Planck Institute for Chemical Physics of Solids DE Germany (DE)

How to cite

APA:

Cano, J., Bradlyn, B., Wang, Z., Elcoro, L., Vergniory, M.G., Felser, C.,... Bernevig, B.A. (2018). Topology of Disconnected Elementary Band Representations. Physical Review Letters, 120(26). https://doi.org/10.1103/PhysRevLett.120.266401

MLA:

Cano, Jennifer, et al. "Topology of Disconnected Elementary Band Representations." Physical Review Letters 120.26 (2018).

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