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Related papers: Optical Phonon Anomaly in Bilayer Graphene with Ul…

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We prove that Electron-phonon coupling (EPC) is the major source of broadening for the Raman G and G- peaks in graphite and metallic nanotubes. This allows us to directly measure the optical-phonon EPCs from the G and G- linewidths. The…

Materials Science · Physics 2007-05-23 Michele Lazzeri , S. Piscanec , Francesco Mauri , A. C. Ferrari , J. Robertson

Electron-phonon coupling in magic-angle twisted bilayer graphene is an important but difficult topic. We propose a scheme to simplify and understand this problem. Weighted by the coupling strength with the low-energy heavy electrons ($f$…

Mesoscale and Nanoscale Physics · Physics 2025-04-17 Hao Shi , Wangqian Miao , Xi Dai

First-principles studies of the electron-phonon coupling in graphene predict a high coupling strength for the $\sigma$ band with $\lambda$ values of up to 0.9. Near the top of the $\sigma$ band, $\lambda$ is found to be $\approx 0.7$. This…

Mesoscale and Nanoscale Physics · Physics 2017-02-28 Federico Mazzola , Thomas Frederiksen , Thiagarajan Balasubramanian , Philip Hofmann , Bo Hellsing , Justin W. Wells

Unlike in ordinary metals, in graphene, phonon structure can be seen in the quasiparticle electronic density of states, because the latter varies on the scale of the phonon energy. In a magnetic field, quantization into Landau levels…

Mesoscale and Nanoscale Physics · Physics 2015-05-28 Adam Pound , J. P. Carbotte , E. J. Nicol

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…

Mesoscale and Nanoscale Physics · Physics 2010-01-26 M. Bianchi , E. D. L. Rienks , S. Lizzit , A. Baraldi , R. Balog , L. Hornekaer , Ph. Hofmann

We investigate the Fano-type line shape of the Ba mode of Y_{1-x}Ca_xBa_2Cu_3O_{6+y} films observed in Raman spectra with A_1g symmetry. The line shape is described with an extended Fano formula that allows us to obtain the bare phonon…

Superconductivity · Physics 2015-06-25 A. Bock , S. Ostertun , K. -O. Subke

We report phonon renormalisation in bilayer graphene as a function of doping. The Raman G peak stiffens and sharpens for both electron and hole doping, as a result of the non-adiabatic Kohn anomaly at the $\Gamma$ point. The bilayer has two…

Mesoscale and Nanoscale Physics · Physics 2015-05-13 A. Das , B. Chakraborty , S. Piscanec , S. Pisana , A. K. Sood , A. C. Ferrari

We report first-principles calculations of the electronic band structure and lattice dynamics for the new superconductor MgB$_{2}$. The excellent agreement between theory and our inelastic neutron scattering measurements of the phonon…

By comparing with recently available experimental data from several groups, we critically discuss the manifestation of continuum many body interaction effects in twisted bilayer graphene (tBLG) with small twist angles and low carrier…

Mesoscale and Nanoscale Physics · Physics 2020-06-02 Sankar Das Sarma , Fengcheng Wu

Density-functional calculations of the phonon spectrum and electron-phonon coupling in MgB$_2$ are presented. The $E_{2g}$ phonons, which involve in-plane B displacements, couple strongly to the $p_{x,y}$ electronic bands. The isotropic…

Superconductivity · Physics 2009-11-07 Amy Y. Liu , I. I. Mazin , Jens Kortus

The coupling between electrons and phonons is one of the fundamental interactions in solids, underpinning a wide range of phenomena such as resistivity, heat conductivity, and superconductivity. However, direct measurements of this coupling…

The anomalous features of the Raman spectroscopy measurement in MgB$_2$ represent a still unresolved puzzle. In particular highly debated are the origin of the huge $E_{2g}$ phonon linewidth, the nature of the low energy ($\omega <…

Superconductivity · Physics 2009-11-11 E. Cappelluti

We investigate the dynamical effects of electron-phonon coupling (EPC) on the superconducting properties of two-dimensional (2D) systems, calculating the Eliashberg function in terms of dynamically renormalized phonons. By studying…

Superconductivity · Physics 2025-04-29 Juraj Krsnik , Dino Novko , Osor Slaven Barišić

First-principles calculations of the electronic structure and vibrational modes, in a system of graphene bilayers and trilayers intercalated with alkaline earth atoms, are resented. It is found that, in similarity to the case of…

Superconductivity · Physics 2011-07-12 R. A. Jishi , D. M. Guzman , H. M. Alyahyaei

It has been predicted that application of a strong electric field perpendicular to the plane of bilayer graphene can induce a significant band gap. We have measured the optical conductivity of bilayer graphene with an efficient electrolyte…

Mesoscale and Nanoscale Physics · Physics 2015-05-13 Kin Fai Mak , Chun Hung Lui , Jie Shan , Tony F. Heinz

We present a self-consistent analysis of the photoemission spectral function A(k, w) of graphene monolayers grown epitaxially on SiC(0001). New information derived from spectral intensity anomalies (in addition to linewidths and peak…

Strongly Correlated Electrons · Physics 2008-09-25 Jessica L. McChesney , Aaron Bostwick , Taisuke Ohta , Konstantin Emtsev , Thomas Seyller , Karsten Horn , Eli Rotenberg

Many crystalline solids possess strongly anharmonic soft phonon modes characterized by diminishing frequency as temperature approaches a critical point associated with a symmetry breaking phase transition. While electron-soft phonon…

We show how coupling to an Einstein phonon $\omega_E$ affects the absorption peaks seen in the optical conductivity of graphene under a magnetic field $B$. The energies and widths of the various lines are shifted, and additional peaks arise…

Mesoscale and Nanoscale Physics · Physics 2015-06-04 Adam Pound , J. P. Carbotte , E. J. Nicol

Gate-modulated low-temperature Raman spectra reveal that the electric field effect (EFE), pervasive in contemporary electronics, has marked impacts on long wavelength optical phonons of graphene. The EFE in this two dimensional honeycomb…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 Jun Yan , Yuanbo Zhang , Philip Kim , Aron Pinczuk

Here, we investigate phonon mode- and electron band-selective electron-phonon couplings in centrosymmetric 1T$'$-MoTe$_2$ using time- and angle-resolved photoemission spectroscopy combined with frequency-domain analysis. Femtosecond…

Materials Science · Physics 2026-02-24 Carl E. Jensen , Christoph Emeis , Stephan Jauernik , Petra Hein , Fabio Caruso , Michael Bauer