2019/04/16 by Ziming Zhu, Zhi‐Ming Yu, Zhi-Ming Yu +5 · 19 citations
Materials Science · Mathematics · Physics and Astronomy · #2D Materials and Applications #Band gap #Brillouin zone #Condensed matter physics #Dirac (video compression format) #Fermi Gamma-ray Space Telescope #Fermi level #Geometry #Graphene research and applications #Mathematics #Mirror symmetry #Physics #Quantum mechanics #Semimetal #Symmetry (geometry) #Topological Materials and Phenomena #Topological insulator #Topology (electrical circuits) #cond-mat.mes-hall
paper · pdf · doi:10.1103/physrevb.100.161401
published in Physical review. B./Physical review. B 100(16) (American Physical Society)
arxiv created 2019/04/16 · openalex created_date 2019/06/27 · openalex publication_date 2019/10/11 · arxiv updated 2019/10/16 · openalex updated_date 2026/08/06
Weak topological insulators and Dirac semimetals are gapped and nodal phases with distinct topological properties, respectively. Here, we propose a topological phase that exhibits features of both and is dubbed composite Dirac semimetal (CDSM). In its bulk, the CDSM has a pair of Dirac points and a pair of bands inverted along a high-symmetry path. At side surfaces, a pair of Fermi arcs connecting the projected Dirac points coexist with a pair of Fermi loops traversing the surface Brillouin zone. A nonsymmorphic symmetry dictates degeneracies between the Fermi arcs and the Fermi loops. We characterize the CDSM by multiple topological invariants and show that, under a transition without breaking any symmetry, it deforms into a topological crystalline insulator hosting two pairs of surface Fermi loops. We demonstrate the CDSM in two models and predict its realization in the KAuTe-family materials.