相关论文: Kohn Anomalies in Graphene Nanoribbons

In this paper, optical properties of Chiral Graphene Nanoribbons both in longitude and transverse polarization have been studied using density functional theory calculation. It has been shown that the selection rule which have been reported…

Vibrational properties of graphene nanoribbons are examined with density functional based tight-binding method and non-resonant bond polarization theory. We show that the recently discovered reconstructed zigzag edge can be identified from…

We study the variations of electron-phonon coupling and their spectroscopic consequences in response to sliding of two layers in bilayer graphene using first-principles calculations and a model Hamiltonian. Our study shows that the long…

An interesting property of zigzag graphene nanoribbons is the presence of edge states which are extended along its borders but localized in the transverse direction. We show that because of this property, electron transport through an…

Quantum confinement and interference often generate exotic properties in nanostructures. One recent highlight is the experimental indication of a magnetic phase transition in zigzag-edged graphene nanoribbons at the critical ribbon width of…

We investigate from first principles the electronic and optical properties of edge-modulated armchair graphene nanoribbons, including both quasi-particle corrections and excitonic effects. Exploiting the oscillating behavior of the ribbon…

The lineshapes of the Raman excitation profiles for radial breathing modes in carbon nanotubes are shown to be strongly affected by interference effects that arise whenever strong optical transitions are separated by a small energy. This is…

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 investigate, in the framework of macroscopic Dirac model, the spectrum, charge density and conductivity of metallic armchair graphene nanoribbons in presence of different mass terms. We reveal the conditions and symmetries governing 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 study vibrational states localized at the edges of graphene nanoribbons. Such surface oscillations can be considered as a phonon analog of Tamm states well known in the electronic theory. We consider both armchair and zigzag graphene…

The quantum corrections to the frequencies of the $\Gamma$ point longitudinal optical (LO) and transverse optical (TO) phonon modes in carbon nanotubes are investigated theoretically. The frequency shift and broadening of the TO phonon mode…

The deformation and disintegration of a graphene nanoribbon under external electrostatic fields are investigated by first principle quantum mechanical calculations to establish its stability range. The zigzag edges terminated by various…

We derive the frequency shifts and the broadening of $\Gamma$ point longitudinal optical (LO) and transverse optical (TO) phonon modes, due to electron-phonon interaction, in graphene under uniaxial strain as a function of the electron…

The honeycomb carbon structure of graphene and nanotubes has a dynamics which can give rise to a spectrum. This can be excited via the interaction with an external electromagnetic field. In this work, non-linear waves on graphene and…

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…

We investigated the atomic structures, Raman spectroscopic and electrical transport properties of individual graphene nanoribbons (GNRs, widths ~10-30 nm) derived from sonochemical unzipping of multi-walled carbon nanotubes (MWNTs).…

We present a theoretical study on narrow armchair graphene nanoribbons (AGNRs) with hydroxyl functionalized edges. Although this kind of passivation strongly affects the structure of the ribbon, a high degree of edge functionalization…

We present some computational simulations of graphene-based nanoribbons with a number of half-twists varying from 0 to 4 and two types of defects obtained by removing a single carbon atom from two different sites. Optimized geometries are…

Properties in magnetic ordered states of graphene nanoribbons with zigzag shaped edges are investigated by applying mean-field approximation to the Hubbard model with on-site repulsion $U$. We observe that magnetic moments and critical…