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Related papers: Chirality-induced Dynamic Kohn Anomalies in Graphe…

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We present the full in-plane phonon dispersion of graphite obtained from inelastic x-ray scattering, including the optical and acoustic branches, as well as the mid-frequency range between the $K$ and $M$ points in the Brillouin zone, where…

Materials Science · Physics 2009-11-13 M. Mohr , J. Maultzsch , E. Dobardzic , S. Reich , I. Milosevic , M. Damnjanovic , A. Bosak , M. Krisch , C. Thomsen

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…

Materials Science · Physics 2007-05-23 Srijan Kumar Saha , U. V. Waghmare , H. R. Krishnamurthy , A. K. Sood

Single-layer graphene sheets are typically characterized by long-wavelength corrugations (ripples) which can be shown to be at the origin of rather strong potentials with both scalar and vector components. We present an extensive…

Mesoscale and Nanoscale Physics · Physics 2010-04-06 Marco Gibertini , Andrea Tomadin , Marco Polini , A. Fasolino , M. I. Katsnelson

Graphene is known as the strongest 2D material in nature, yet we show that moderate charge doping of either electrons or holes can further enhance its ideal strength by up to ~17%, based on first principles calculations. This unusual…

Materials Science · Physics 2015-06-11 Chen Si , Wenhui Duan , Zheng Liu , Feng Liu

We introduce a different perspective describing electron-phonon interactions in graphene based on curved space hydrodynamics. Interactions of phonons with charge carriers increase the electrical resistivity of the material. Our approach…

Materials Science · Physics 2017-02-15 Ilario Giordanelli , Miller Mendoza , Hans Herrmann

We report the observation of an intense anomalous peak at 1608 cm$^{-1}$ in the Raman spectrum of graphene associated to the presence of chromium nanoparticles in contact with graphene. Bombardment with an electron beam demonstrates that…

While many physical properties of graphene can be understood qualitatively on the basis of bare Dirac bands, there is specific evidence that electron-electron (EE) and electron-phonon (EP) interactions can also play an important role. We…

Strongly Correlated Electrons · Physics 2015-06-04 J. P. F. LeBlanc , Jungseek Hwang , J. P. Carbotte

The phonon density of states (DOS) of graphene with different types of point defects (carbon isotopes, substitution atoms, vacancies) is considered. Using a solvable model which is based on the harmonic approximation and the assumption that…

Materials Science · Physics 2010-12-21 Vadym M Adamyan , Vladimir V Zavalniuk

The high-frequency Raman-active phonon modes of metallic single-walled carbon nanotubes (SWNTs) are thought to be characterized by Kohn anomalies (KAs), which are expected to be modified by the doping-induced tuning of the Fermi energy…

Soft Condensed Matter · Physics 2007-05-23 Nicolas Caudal , A. Marco Saitta , Michele Lazzeri , Francesco Mauri

Radio-frequency compressed ultrafast electron diffraction has been used to probe the coherent and incoherent coupling of impulsive electronic excitation at 1.55 eV (800 nm) to optical and acoustic phonon modes directly from the perspective…

Materials Science · Physics 2015-06-23 Robert P. Chatelain , Vance R. Morrison , Bart L. M. Klarenaar , Bradley J. Siwick

A deformation of a graphene sheet changes more than the positions of the atoms. In the low-energy Dirac theory it also produces geometric electron-phonon vertices. One of these vertices acts as an emergent phonon gauge field, $\calA_\mu$,…

Strongly Correlated Electrons · Physics 2026-05-19 Ara Sedrakyan

We theoretically consider the effect of plasmon collective modes on the frequency-dependent conductivity of graphene in the presence of the random static potential of charged impurities. We develop an equation of motion approach suitable…

Mesoscale and Nanoscale Physics · Physics 2013-08-09 K. Kechedzhi , S. Das Sarma

We present a first-principles investigation of the phonon-induced electron self-energy in graphene. The energy dependence of the self-energy reflects the peculiar linear bandstructure of graphene and deviates substantially from the usual…

Materials Science · Physics 2007-08-23 Cheol-Hwan Park , Feliciano Giustino , Marvin L. Cohen , Steven G. Louie

We present a detailed study of the vibrational properties of Single Wall Carbon Nanotubes (SWNTs). The phonon dispersions of SWNTs are strongly shaped by the effects of electron-phonon coupling. We analyze the separate contributions of…

Materials Science · Physics 2007-07-10 Stefano Piscanec , Michele Lazzeri , John Robertson , Andrea Carlo Ferrari , Francesco Mauri

We address the computation of physical observables in graphene in the presence of Coulomb interactions of density-density type modeled with a static Coulomb potential within a quantum field theory perturbative renormalization scheme. We…

Strongly Correlated Electrons · Physics 2012-03-22 Fernando de Juan , Adolfo G. Grushin , Maria A. H. Vozmediano

Herein, intervalley scattering is exploited to account for anomalous antiresonances in the infrared spectra of doped and disordered single layer graphene. We present infrared spectroscopy measurements of graphene grafted with iodophenyl…

We compute, from first-principles, the frequency of the E2g, Gamma phonon (Raman G-band) of graphene, as a function of the charge doping. Calculations are done using i) the adiabatic Born-Oppenheimer approximation and ii) time-dependent…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Michele Lazzeri , Francesco Mauri

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…

Materials Science · Physics 2007-10-25 Nicola Bonini , Michele Lazzeri , Nicola Marzari , Francesco Mauri

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…

Materials Science · Physics 2008-12-23 Cheol-Hwan Park , Feliciano Giustino , Marvin L. Cohen , Steven G. Louie

We theoretically study various aspects of the electron-surface optical phonon interaction effects in graphene on a substrate made of polar materials. We calculate the electron self-energy in the presence of the surface phonon-mediated…

Mesoscale and Nanoscale Physics · Physics 2013-03-25 E. H. Hwang , S. Das Sarma