DOI

  • Boris V. Senkoyskiy
  • Tomas Marangoni
  • Danny Haberer
  • Cesare Tresca
  • Gianni Profeta
  • Vasile Caciuc
  • Shigeru Tsukamoto
  • Nicolae Atodiresei
  • Niels Ehlen
  • Chaoyu Chen
  • Jose Avila
  • Maria C. Asensio
  • Andrei Yu. Varykhalov
  • Alexei Nefedov
  • Christof Woell
  • Timur K. Kim
  • Moritz Hoesch
  • Felix R. Fischer
  • Alexander Grueneis

We investigate the electronic and vibrational properties of bottom-up synthesized aligned armchair graphene nanoribbons of N = 7 carbon atoms width periodically doped by substitutional boron atoms (B-7AGNRs). Using angle-resolved photoemission spectroscopy and density functional theory calculations, we find that the dopant-derived valence and conduction band states are notably hybridized with electronic states of Au substrate and spread in energy. The interaction with the substrate leaves the bands with pure carbon character rather unperturbed. This results in an identical effective mass of approximate to 0.2 m(0) for the next-highest valence band compared with pristine 7AGNRs. We probe the phonons of B-7AGNRs by ultrahigh-vacuum (UHV) Raman spectroscopy and reveal the existence of characteristic splitting and red shifts in Raman modes due to the presence of substitutional boron atoms. Comparing the Raman spectra for three visible lasers (red, green, and blue), we find that interaction with gold suppresses the Raman signal from B-7AGNRs and the energy of the green laser (2.33 eV) is closer to the resonant E-22 transition. The hybridized electronic structure of the B-7AGNR-Au interface is expected to improve electrical characteristics of contacts between graphene nanoribbon and Au. The Raman fingerprint allows the easy identification of B-7AGNRs, which is particularly useful for device fabrication.

Original languageEnglish
Pages (from-to)7571-7582
Number of pages12
JournalACS Nano
Volume12
Issue number8
DOIs
StatePublished - 28 Aug 2018

    Scopus subject areas

  • Engineering(all)
  • Physics and Astronomy(all)
  • Materials Science(all)

    Research areas

  • graphene nanoribbons, boron doping, electronic structure, ARPES, Raman, substrate interaction, ON-SURFACE SYNTHESIS, BOTTOM-UP FABRICATION, BAND-GAP, CRYSTALLITE SIZE, SPECTROSCOPY, ARMCHAIR, HETEROJUNCTIONS, SEMICONDUCTORS, SCATTERING, ENERGY

ID: 33794311