English

Tip induced doping effects in local tunnel spectra of graphene

Mesoscale and Nanoscale Physics 2014-02-11 v1

Abstract

We report on tip induced doping in local tunnel spectra of single layer graphene (SLG) with tunable back-gate using room temperature scanning tunneling microscopy and spectroscopy (STM/S). The SLG samples, prepared on silicon dioxide surface by exfoliation method and verified by Raman spectra, show atomically resolved honeycomb lattice. Local tunnel spectra show two minima with a clear evolution in the position of both with doping by the back gate. A similar variation in spectra is also observed spatially due to charge inhomogeneity. With doping the two minima move in opposite directions with one showing nearly a square root dependence and the other a linear dependence on gate voltage. We explain these features as arising from the STM tip induced and bias voltage dependent doping in SLG.

Keywords

Cite

@article{arxiv.1008.3606,
  title  = {Tip induced doping effects in local tunnel spectra of graphene},
  author = {Shyam K. Choudhury and Anjan K. Gupta},
  journal= {arXiv preprint arXiv:1008.3606},
  year   = {2014}
}

Comments

4 pages, 5 figures