Electronic properties of two-dimensional hexagonal germanium

摘要

The electronic properties of two-dimensional hexagonal germanium, so called germanene, areninvestigated using first-principles simulations. Consistent with previous reports, the surface isnpredicted to have a “poor” metallic behavior, i.e., being metallic with a low density of states at thenFermi level. It is found that biaxial compressively strained germanene is a gapless semiconductornwith linear energy dispersions near the K points—like graphene. The calculated Fermi velocity ofngermanene is almost independent of the strain and is about 1.7u0001106nm/ s, quite comparable to thenvalue in graphene. © 2010 American Institute of Physics. u0003doi:10.1063/1.3332588