Dirac fermions in borophene

Abstract

Honeycomb structures of group IV elements can host massless Dirac fermions with non-trivial Berry phases. Their potential for electronic applications has attracted great interest and spurred a broad search for new Dirac materials especially in monolayer structures. We present a detailed investigation of the β12 boron sheet, which is a borophene structure that can form spontaneously on a Ag(111) surface. Our tight-binding analysis revealed that the lattice of the β12-sheet could be decomposed into two triangular sublattices in a way similar to that for a honeycomb lattice, thereby hosting Dirac cones. Furthermore, each Dirac cone could be split by introducing periodic perturbations representing overlayer-substrate interactions. These unusual electronic structures were confirmed by angle-resolved photoemission spectroscopy and validated by first-principles calculations. Our results suggest monolayer boron as a new platform for realizing novel high-speed low-dissipation devices.

accepted for publication in Physical Review Letters

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Cited by in corpus (6)

• Two-dimensional Spin-Orbit Dirac Point in Monolayer HfGeTe
• Two-Dimensional Semiconducting Boron Monolayers
• Signature of tilted Dirac cones in Weiss oscillations of $8-Pmmn$ borophene
• Interplay between topology and disorder in a two-dimensional semi-Dirac material
• Engineering Dirac states in graphene: Coexisting type-I and type-II Floquet-Dirac fermions
• Dirac cones in Two-dimensional Borane