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Related papers: Phonon dispersion in graphene

200 papers

Using a first-principles approach we calculate the acoustic electron-phonon couplings in graphene for the transverse (TA) and longitudinal (LA) acoustic phonons. Analytic forms of the coupling matrix elements valid in the long-wavelength…

Materials Science · Physics 2013-11-22 Kristen Kaasbjerg , Kristian S. Thygesen , Karsten W. Jacobsen

We investigate the transport of electrons in disordered and pristine graphene devices. Fano shot noise, a standard metric to assess the mechanism for electronic transport in mesoscopic devices, has been shown to produce almost the same…

Mesoscale and Nanoscale Physics · Physics 2013-09-18 Mario F. Borunda , H. Hennig , Eric J. Heller

The interaction of graphene with metallic substrates reveals phenomena and properties of great relevance for applications in nanotechnology. In this review, the vibrational characterization by means of various inelastic scattering…

Materials Science · Physics 2016-01-08 Antonio Politano

In this article we have reproduced the tight binding $\pi$ band dispersion of graphene including upto third nearest neighbours and also calculated the partial density of states (due to $\pi$ band only) within the same model. The aim was to…

Materials Science · Physics 2009-07-27 Rupali Kundu

Bi-layer graphene with a twist angle \theta\ between the layers generates a superlattice structure known as Moir\'{e} pattern. This superlattice provides a \theta-dependent q wavevector that activates phonons in the interior of the…

Mesoscale and Nanoscale Physics · Physics 2013-03-29 J. Campos-Delgado , L. G. Cançado , C. A. Achete , A. Jorio , J. -P. Raskin

We apply standard, first-principles calculations to a complete treatment of lattice dynamics in the harmonic approximation. The algorithm makes use of the straightforward ``frozen-phonon'' approach to the calculation of vibrational spectra…

Materials Science · Physics 2007-05-23 Hadley M. Lawler , Eric K. Chang , Eric L. Shirley

Graphite is a well-studied material with known electronic and optical properties. Graphene, on the other hand, which is just one layer of carbon atoms arranged in a hexagonal lattice, has been studied theoretically for quite some time but…

Mesoscale and Nanoscale Physics · Physics 2015-05-13 F. Molitor , D. Graf , C. Stampfer , T. Ihn , K. Ensslin

The crystal structure and phonon dynamics of pentacene is computed with the Quasi Harmonic Lattice Dynamics (QHLD) method, based on atom-atom potential. We show that two crystalline phases of pentacene exist, rather similar in thermodynamic…

The theory of Raman scattering by the electron--phonon coupled system in metals and heavily doped semiconductors is developed taking into account the Coulomb screening and the electron--phonon deformation interaction. The Boltzmann equation…

Materials Science · Physics 2009-11-10 L. Falkovsky

Conduction between graphene layers is suppressed by momentum conservation whenever the layer stacking has a rotation. Here we show that phonon scattering plays a crucial role in facilitating interlayer conduction. The resulting dependence…

Mesoscale and Nanoscale Physics · Physics 2015-06-12 V. Perebeinos , J. Tersoff , Ph. Avouris

Many promising optoelectronic devices, such as broadband photodetectors, nonlinear frequency converters, and building blocks for data communication systems, exploit photoexcited charge carriers in graphene. For these systems, it is…

Using very uniform large scale chemical vapor deposition grown graphene transferred onto silicon, we were able to identify 15 distinct Raman lines associated with graphene monolayers. This was possible thanks to a combination of different…

Mesoscale and Nanoscale Physics · Physics 2012-11-07 Simon Bernard , Eric Whiteway , Victor Yu , D. G. Austing , Michael Hilke

Graphene grain boundaries are known to affect phonon transport and thermal conductivity, suggesting that they may be used to engineer the phononic properties of graphene. Here, the effect of two buckled grain boundaries on long-wavelength…

Mesoscale and Nanoscale Physics · Physics 2015-06-11 Edit E. Helgee , Andreas Isacsson

The temperature dependence of the mobility in suspended graphene samples is investigated. In clean samples, flexural phonons become the leading scattering mechanism at temperature $T \gtrsim 10\,\,$K, and the resistivity increases…

In this work we study the symmetry properties of electrons and phonons in graphene systems as function of the number of layers. We derive the selection rules for the electron-radiation and for the electron-phonon interactions at all points…

Mesoscale and Nanoscale Physics · Physics 2013-06-20 L. M. Malard , D. L. Mafra , M. H. D. Guimarães , M. S. C. Mazzoni , A. Jorio

The effect of pressure on the zone-center optical phonon modes and the elastic properties of hafnium has been studied by both experimental (Raman scattering) and theoretical (DFT) approaches. It was found an anomaly dependence of the phonon…

Materials Science · Physics 2018-06-06 D. Novoselov , V. I. Anisimov , Yu. S. Ponosov

We analyze intrinsic nonlinearities in two-dimensional polaritonic materials interacting with an optical wave. Focusing on the case of graphene, we show that the second-order nonlinear optical conductivity due to carrier density…

Mesoscale and Nanoscale Physics · Physics 2019-07-24 Christian Wolff , Christos Tserkezis , N. Asger Mortensen

We report a simple safe and attractive pedagogic demonstration with magnetic compasses that facilitates an intuitive understanding of the concept that ferromagnetism and ferroelectricity do not result from dipole-dipole interactions alone.…

We study inelastic energy relaxation in graphene for low energies to find out how electrons scatter with acoustic phonons and other electrons. By coupling the graphene to superconductors, we create a strong dependence of the measured…

Mesoscale and Nanoscale Physics · Physics 2015-05-27 Juha Voutilainen , Aurelien Fay , Pasi Häkkinen , Janne K. Viljas , Tero T. Heikkilä , Pertti J. Hakonen

We show that the delivery of fracture work to the tip of an advancing planar crack is strongly reduced by surface phonon emission, leading to forbidden ranges of crack speed. The emission can be interpreted through dispersion of the group…

Materials Science · Physics 2009-11-07 Andrea Parisi , Robin C. Ball