Related papers: Phonon renormalisation in doped bilayer graphene
Strong electron-phonon interaction which limits electronic mobility of semiconductors can also have significant effects on phonon frequencies. The latter is the key to the use of Raman spectroscopy for nondestructive characterization of…
Here we use pristine graphene samples in order to analyze how the Raman peaks intensity, measured at 2.4 eV and 1.96 eV excitation energy, changes with the amount of doping. The use of pristine graphene allows investigating the intensity…
We report strong variations in the Raman spectra for different single-layer graphene samples obtained by micromechanical cleavage, which reveals the presence of excess charges, even in the absence of intentional doping. Doping…
We present a new way to tune the electron-phonon coupling (EPC) in graphene by changing the deformation potential with electron/hole doping. We show the EPC for highest optical branch at the high symmetry point K, acquires a strong…
We investigate the evolution of the Raman spectrum of defected graphene as a function of doping. Polymer electrolyte gating allows us to move the Fermi level up to 0.7eV, as monitored by \textit{in-situ} Hall-effect measurements. For a…
We demonstrate theoretically that quantum dots in bilayers of graphene can be realized. A position-dependent doping breaks the equivalence between the upper and lower layer and lifts the degeneracy of the positive and negative momentum…
We have investigated antidot lattices, which were prepared on exfoliated graphene single layers via electron-beam lithography and ion etching, by means of scanning Raman spectroscopy. The peak positions, peak widths and intensities of the…
The interaction of electron-hole pairs with lattice vibrations exhibits a wealth of intriguing physical phenomena. The Kohn anomaly is a renowned example where electron-phonon coupling leads to non-analytic phonon dispersion at specific…
We use first-principles density-functional calculations to determine the frequency shift of the A$'_1$-${\bf K}$ phonon (Raman D band) in monolayer graphene, as a function of the charge doping. A detailed DFT study on the electron-phonon…
The phonon dispersion of graphene on Ir(111) has been determined by means of angle-resolved inelastic electron scattering and density functional calculations. Kohn anomalies of the highest optical-phonon branches are observed at the…
The stacking faults (deviates from Bernal) will break the translational symmetry of multilayer graphenes and modify their electronic and optical behaviors to the extent depending on the interlayer coupling strength. This paper addresses the…
Cyclotron resonance in graphene is studied with focus on many-body corrections to the resonance energies, which evade Kohn's theorem. The genuine many-body corrections turn out to derive from vacuum polarization, specific to graphene, which…
Using first-principles techniques, we calculate the renormalization of the electron Fermi velocity and the vibrational lifetimes arising from electron-phonon interactions in doped bilayer graphene and in graphite and compare the results…
Fano resonances and their strong doping dependence are observed in Raman scattering of single-layer graphene (SLG). As the Fermi level is varied by a back-gate bias, the Raman G band of SLG exhibits an asymmetric line shape near the charge…
We derive core-level spectra for doped free-standing bilayer graphene. Numerical results are presented for all nine combinations of the doping concentrations $10^{12}\rm{cm}^{-2}$, $10^{13}\rm{cm}^{-2}$, and $10^{14}\rm{cm}^{-2}$ in the two…
We report an experimental Raman study of few-layer graphene after chemical doping achieved by a plasma process in CHF$_3$ gas. A systematic reduction of both the splitting and the area of the 2D band is observed with increasing the doping…
We study how phonon structure manifests itself in the electronic density of states of graphene. A procedure for extracting the value of the electron-phonon renormalization $\lambda$ is developed. In addition, we identify direct phonon…
Twisted bilayer graphene (TBG) has attracted great interest in the last decade due to the novel properties it exhibited. It was revealed that e-phonon interaction plays an important role in a variety of phenomena in this system, such as…
We analyze renormalization of the pi band of n-doped epitaxial graphene on Ir(111) induced by electron-phonon coupling. Our procedure of extracting the bare band relies on recursive self-consistent refining of the functional form of the…
The electron-phonon coupling in potassium-doped graphene on Ir(111) is studied via the renormalization of the pi* band near the Fermi level, using angle-resolved photoemission spectroscopy. The renormalization is found to be fairly weak and…