• 文献标题:   Suppression of electron scattering resonances in graphene by quantum dots
  • 文献类型:   Article
  • 作  者:   KRIVENKOV M, MARCHENKO D, SANCHEZBARRIGA J, RADER O, VARYKHALOV A
  • 作者关键词:  
  • 出版物名称:   APPLIED PHYSICS LETTERS
  • ISSN:   0003-6951 EI 1077-3118
  • 通讯作者地址:   Helmholtz Zentrum Berlin Mat Energie
  • 被引频次:   4
  • DOI:   10.1063/1.4994193
  • 出版年:   2017

▎ 摘  要

Transmission of low-energetic electrons through two-dimensional materials leads to unique scattering resonances. These resonances contribute to photoemission from occupied bands where they appear as strongly dispersive features of suppressed photoelectron intensity. Using angle-resolved photoemission, we have systematically studied scattering resonances in epitaxial graphene grown on the chemically differing substrates Ir(111), Bi/Ir, and Ni(111) as well as in graphene/Ir(111) nanopatterned with a superlattice of uniform Ir quantum dots. While the strength of the chemical interaction with the substrate has almost no effect on the dispersion of the scattering resonances, their energy can be controlled by the magnitude of charge transfer from/to graphene. At the same time, a superlattice of small quantum dots deposited on graphene eliminates the resonances completely. We ascribe this effect to a nanodot-induced buckling of graphene and its local rehybridization from sp(2) to sp(3) towards a three-dimensional structure. Our results suggest nanopatterning as a prospective tool for tuning optoelectronic properties of two-dimensional materials with a graphene-like structure. Published by AIP Publishing.