Related papers: Ising instability of a Holstein phonon mode in gra…
We study the thermal distribution of intervalley phonons in a graphene sheet. These phonons have two components with the same frequency. The degeneracy of the two modes is preserved by weak electron-phonon coupling. A sufficiently strong…
Taking into account the constraints imposed by the lattice symmetry, the phonon dispersion is calculated for graphene with interactions between the first and second nearest neighbors in the framework of the Born-von Karman model. Analytical…
Inelastic phonon scattering in graphene field-effect transistors (FETs) is studied by numerically solving the Boltzmann transport equation in three dimensional real and phase spaces (x, kx, ky). A kink behavior due to ambipolar transport…
The lattice thermal conductivity of graphene is evaluated using a microscopic model that takes into account the lattice's discrete nature and the phonon dispersion relation within the Brillouin zone. The Boltzmann transport equation is…
Taking into account the constraints imposed by the lattice symmetry, we calculate the phonon dispersion for graphene with interactions between the first, second, and third nearest neighbors in the framework of the Born--von Karman model.…
Properties of phonons - quanta of the crystal lattice vibrations - in graphene have attracted strong attention of the physics and engineering communities. Acoustic phonons are the main heat carriers in graphene near room temperature while…
Classical thermal transport theories that preserve rotational symmetry, predict strong anharmonic scattering of out-of-plane lattice vibrational modes called flexural phonons in flat suspended graphene sheets. Such strong scattering…
Electrical properties of multi-layer graphene are subject to variations due to random interlayer alignments. In this work we reported graphene interlayer conductance without special layer aligning. Ohmic contacts between two graphene layers…
We have implemented a generic method, based on the 2n+1 theorem within density functional perturbation theory, to calculate the anharmonic scattering coefficients among three phonons with arbitrary wavevectors. The method is used to study…
We determine from first-principles the finite-temperature properties--linewidths, line shifts, and lifetimes--of the key vibrational modes that dominate inelastic losses in graphitic materials. In graphite, the phonon linewidth of the…
Understanding the mechanisms of thermal conduction in graphene is a long-lasting research topic, due to its high thermal conductivity. Peierls-Boltzmann transport equation (PBTE) based studies have revealed many unique phonon transport…
Topological phase transitions occur when the electronic bands change their topological properties, typically featuring the closing of the bandgap. While the influence of topological phase transitions on electronic and optical properties has…
The out-of-plane fluctuations of carbon atoms in a graphene sheet have been studied by means of classical molecular dynamic simulations with an empirical force-field as a function of temperature. The Fourier analysis of the out-of-plane…
Ripples in pristine freestanding graphene naturally orient themselves in an array that is alternately curved-up and curved-down; maintaining an average height of zero. Using scanning tunneling microscopy (STM) to apply a local force, the…
We report on the temperature dependent electron transport in graphene at different carrier densities $n$. Employing an electrolytic gate, we demonstrate that $n$ can be adjusted up to 4$\times10^{14}$cm$^{-2}$ for both electrons and holes.…
We study the effect exerted by the electrons on the flexural phonons in graphene, accounting for the attractive interaction created by the exchange of electron-hole excitations. Combining the self-consistent computation of the phonon…
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…
Suspended graphene exhibits ripples of size ranging from 50 to 100 {\AA} and height $\sim$10{\AA}, however, their origin remains undetermined. Previous theoretical works have proposed that rippling in graphene might be generated by the…
The two-dimensional mapping of the phonon dispersions around the $K$ point of graphite by inelastic x-ray scattering is provided. The present work resolves the longstanding issue related to the correct assignment of transverse and…
The acoustic, optic, and surface polar optic phonons are the three important intrinsic and extrinsic phononic modes that increasingly populate graphene on a substrate with rising temperatures; the coupling of which with photoexcited hot…