Two-dimensional honeycomb borophene oxide: Strong anisotropy and nodal loop transformation

Abstract

The search for topological semimetals is mainly focused on heavy-element compounds as following the footsteps of previous research on topological insulators, with less attention on light-element materials. However, the negligible spin orbit coupling with light elements may turn out to be beneficial for realizing topological band features.Here, using first-principles calculations, we propose a new two-dimensional light-element material-the honeycomb borophene oxide (h-B2O), which has nontrivial topological properties.The proposed structure is based on the recently synthesized honeycomb borophene on Al (111) substrate [Sci. Bull. 63, 282 (2018)]. The h-B2O monolayer is completely flat, unlike the oxides of graphene or silicene. We systematically investigate the structural properties of h-B2O, and find that it has very good stability and exhibits significant mechanical anisotropy. Interestingly, the electronic band structure of h-B2O hosts a nodal loop centered around the Y point in the Brillouin zone, protected by the mirror symmetry. Furthermore, under moderate lattice strain, the single nodal loop can be transformed into two loops, each penetrating through the Brillouin zone. The loops before and after the transition are characterized by different Z*Z topological indices. Our work not only predicts a new two-dimensional material with interesting physical properties, but also offers an alternative approach to search for new topological phases in 2D light-element systems.

arXiv comment7 figures, published on Nanoscale

References in corpus (32)

• Experimental Observation of Quantum Hall Effect and Berry's Phase in Graphene
• Quantum Spin Hall Effect in Graphene
• Quantum Spin Hall Effect and Topological Phase Transition in HgTe Quantum Wells
• Electronic Structure of Pyrochlore Iridates: From Topological Dirac Metal to Mott Insulator
• Weyl and Dirac Semimetals in Three Dimensional Solids
• Classification of topological insulators and superconductors in three spatial dimensions
• Topological Materials: Weyl Semimetals
• Colloquium: Topological Band Theory
• Novel Precursors for Boron Nanotubes: The Competition of Two-Center and Three-Center Bonding in Boron Sheets
• Topological Node-Line Semimetal in Three Dimensional Graphene Networks
• Elastic properties of hydrogenated graphene
• Semimetallic Two-Dimensional Boron Allotrope with Massless Dirac Fermions
• Structural and Electronic Properties of Oxidized Graphene
• Dirac fermions in borophene
• Spin-orbit-free Weyl-loop and Weyl-point semimetals in a stable three-dimensional carbon allotrope
• Nodal surface semimetals: Theory and material realization
• Discovery of two-dimensional Dirac nodal line fermions in monolayer Cu2Si
• Towards Three-Dimensional Weyl-SurfaceSemimetals in Graphene Networks
• Type-II nodal loops: theory and material realization
• Nonsymmorphic-symmetry-protected hourglass Dirac loop, nodal line, and Dirac point in bulk and monolayer $X_3$SiTe${}_6$ ($X=$ Ta, Nb)
• Prediction of two-dimensional nodal-line semimetal in a carbon nitride covalent network
• Blue Phosphorene Oxide: Strain-tunable Quantum Phase Transitions and Novel 2D Emergent Fermions
• Dirac and Weyl Materials: Fundamental Aspects and Some Spintronics Applications
• Three-dimensional Pentagon Carbon with a genesis of emergent fermions
• A Gapless MoS${}_2$ Allotrope Possessing Both Massless Dirac and Heavy Fermions
• Two-Dimensional Node-Line Semimetals in a Honeycomb-Kagome Lattice
• Nexus and Dirac lines in topological materials
• Hybrid Nodal Loop Metal: Unconventional Magnetoresponse and Material Realization
• Triplet Fermions and Dirac Fermions in Borophene
• A Family Group of Two-dimensional Node-Line Semimetals
• Semi-Dirac Semimetal in Silicene Oxide
• Two-dimensional topological nodal line semimetal in layered $X_{2}Y$ ($X$ = Ca, Sr, and Ba; $Y$ = As, Sb, and Bi)

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