Resonance Raman Spectrum of Doped Epitaxial Graphene at the Lifshitz Transition

Abstract

We employ ultra-high vacuum (UHV) Raman spectroscopy in tandem with angle-

Combined Ultra High Vacuum Raman and Electronic Transport Characterization of Large‐Area Graphene on SiO2

“…Angle‐resolved photoemission (ARPES) measurements of Gr/Ir(111) are shown in a related publication and confirm the weak p‐doping of graphene/Ir(111) in agreement to literature reporting a Dirac crossing 100 meV above the Fermi level. ARPES moreover confirms that the graphene is monolayer in nature since only a single valence band appears.…”

Origin of the Flat Band in Heavily Cs-Doped Graphene

“…Actually, when less Cs is deposited, we obtain the intercalated √ 3 × √ 3-R30 • phase that we described above [24]. Thus, the graphene layer is encapsulated by one Cs…”

“…We have performed calculations of the Raman spectrum according to previously developed model [58,24]. Raman intensity as a function of Raman shift ω s arises from the interference effect between the phonon G band and the electronic Raman spectra (ERS) causing the Fano resonance [58,24]: Figures 3a, 3b, 3c, and 3d were generated using the pybinding package for python3 [68].…”

“…The doping strongly affects the Raman spectra of epitaxial graphene/Ir(111). The Raman G band shifts down in frequency and assumes a Fano lineshape by alkali-metal doping [24]. The Fano lineshape of the G band in alkali-metal doped graphene has been explained by quantum interference effects in the scattering pathways for vibrational and electronic Raman scattering (ERS) [24].…”

“…The Raman G band shifts down in frequency and assumes a Fano lineshape by alkali-metal doping [24]. The Fano lineshape of the G band in alkali-metal doped graphene has been explained by quantum interference effects in the scattering pathways for vibrational and electronic Raman scattering (ERS) [24]. The relationship of G band frequency and Fano asymmetry (expressed by the parameter 1/q) versus carrier concentration has been probed for carrier concentrations up to the Lifshitz transition [24].…”