Two-dimensional Dirac signature of germanene

Abstract

The structural and electronic properties of germanene coated Ge${}_2$Pt clusters have been determined by scanning tunneling microscopy and spectroscopy at room temperature. The interior of the germanene sheet exhibits a buckled honeycomb structure with a lattice constant of 4.3 Åand a buckling of 0.2 Å. The zigzag edges of germanene are reconstructed and display a 4$\times$ periodicity. The differential conductivity of the interior of the germanene sheet has a V-shape, which is reminiscent of the density of states of a two-dimensional Dirac system. The minimum of the differential conductivity is located close to the Fermi level and has a non-zero value, which we ascribe to the metallic character of the underlying Ge${}_2$Pt substrate. Near the reconstructed germanene zigzag edges the shape of the differential conductivity changes from a V-shape to a more parabolic-like shape, revealing that the reconstructed germanene zigzag edges do not exhibit a pronounced metallic edge state.

References in corpus (5)

• Electric Field Effect in Atomically Thin Carbon Films
• Germanene: a novel two-dimensional Germanium allotrope akin to Graphene and Silicene
• Self-passivating edge reconstructions of graphene
• Group-IV graphene- and graphane-like nanosheets
• Germanene termination of Ge${}_2$Pt crystals on Ge(110)

Cited by in corpus (4)

• Structural and electronic properties of germanene on MoS${}_2$
• Investigation of the atomic and electronic structures of highly ordered two-dimensional germanium on Au(111)
• On the mystery of the absence of a spin-orbit gap in scanning tunneling microscopy spectra of germanene
• Two-dimensional germanium islands with Dirac signature on Ag2Ge surface alloy