Direct Evidence of Dirac Signature in Bilayer Germanene Islands on Cu(111)

Researchers reported the growth of bilayer germanene on Cu(111) demonstrating for the first time the presence of a nearly linear energy dispersion in the vicinity of the Fermi energy. Cu(111) was adopted as the growth template because of its hexagonal symmetry without surface reconstruction, matching lattice, and relatively weaker interfacial interaction with adsorbates than other metals. Atomic structures and electronic characteristics of the obtained germanene were explored by LT-STM/S in combination with first-principles DFT calculations.