Modification of the G-phonon mode of graphene by nitrogen doping
Applied Physics Letters
The effect of nitrogen doping on the phonon spectra of graphene is analyzed. In particular, we employ first-principles calculations and scanning Raman analysis to investigate the dependence of phonon frequencies in graphene on the concentration of nitrogen dopants. We demonstrate that the G phonon frequency shows oscillatory behavior as a function of nitrogen concentration. We analyze different mechanisms which could potentially be responsible for this behavior, such as Friedel charge oscillations around the localized nitrogen impurity atom, the bond length change between nitrogen impurity and its nearest neighbor carbon atoms, and the long-range interactions of the nitrogen point defects. We show that the bond length change and the long range interaction of point defects are possible mechanisms responsible for the oscillatory behavior of the G frequency as a function of nitrogen concentration. At the same time, Friedel charge oscillations are unlikely to contribute to this behavior.
Department of Physics
Original Publication Date
DOI of published version
UNI ScholarWorks, Rod Library, University of Northern Iowa
Lukashev, Pavel V.; Zhao, Liuyan; Paudel, Tula R.; Schiros, Theanne; Hurley, Noah; Tsymbal, Evgeny Y.; Pinczuk, Aron; Pasupathy, Abhay; and He, Rui, "Modification of the G-phonon mode of graphene by nitrogen doping" (2016). Faculty Publications. 1126.