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Related papers: Kohn Anomalies and Electron-Phonon Interaction in …

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Graphene is a model system for the study of electrons confined to a strictly two-dimensional layer1 and a large number of electronic phenomena have been demonstrated in graphene, from the fractional2, 3 quantum Hall effect to…

Mesoscale and Nanoscale Physics · Physics 2015-05-18 Jian-Hao Chen , W. G. Cullen , E. D. Williams , M. S. Fuhrer

Strong electron-phonon interaction which limits electronic mobility of semiconductors can also have significant effects on phonon frequencies. The latter is the key to the use of Raman spectroscopy for nondestructive characterization of…

In superconducting copper oxides some Cu-O bond-stretching phonons around 70meV show anomalous giant softening and broadening of electronic origin and electronic dispersions have large renormalization kinks near the same energy. These…

Superconductivity · Physics 2014-01-27 S. R. Park , T. Fukuda , A. Hamann , D. Lamago , L. Pintschovius , M. Fujita , K. Yamada , D. Reznik

We present ab-initio phonon dispersion relations for the three lead chalcogenides PbS, PbSe, and PbTe. The acoustic branches are in very good agreement with inelastic neutron-scattering data and calculations of the specific heat give good…

Materials Science · Physics 2013-08-07 Ondrej Kilian , Guy Allan , Ludger Wirtz

Recent experiments have shown surprisingly large thermal time constants in suspended graphene ranging from 10 to 100 ns in drums with a diameter ranging from 2 to 7 microns. The large time constants and their scaling with diameter points…

Mesoscale and Nanoscale Physics · Physics 2020-03-18 Robin J. Dolleman , Yaroslav M. Blanter , Herre S. J. van der Zant , Peter G. Steeneken , Gerard J. Verbiest

Intensity of the first- and the second-order Raman spectra are calculated as a function of the Fermi energy. We show that the Kohn anomaly effect, i.e., phonon frequency renormalization, in the first-order Raman spectra originates from the…

Mesoscale and Nanoscale Physics · Physics 2016-08-10 Eddwi H. Hasdeo , Ahmad R. T. Nugraha , Mildred Dresselhaus , Riichiro Saito

We study a question of presence of Kohn points, yielding at low temperatures non-analytic momentum dependence of magnetic susceptibility near its maximum, in electronic spectum of some three-dimensional systems. In particular, we consider…

Strongly Correlated Electrons · Physics 2017-12-05 A. A. Stepanenko , D. O. Volkova , P. A. Igoshev , A. A. Katanin

Optimizing the cooperativity between two distinct particles is an important feature of quantum information processing. Of particular interest is the coupling between spin and phonon, which allows for integrated long range communication…

Applied Physics · Physics 2024-02-16 K. An , C. Kim , K. -W. Moon , R. Kohno , G. Olivetti , G. de Loubens , N. Vukadinovic , J. Ben Youssef , C. Hwang , O. Klein

We measure phonon dispersion and linewidth in a single crystal of MgB_2 along the Gamma-A, Gamma-M and A-L directions using inelastic X-Ray scattering. We use Density Functional Theory to compute the effect of both electron-phonon coupling…

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 study the valence crossover and strong electron-phonon coupling of EuPd$_2$Si$_2$ by polarization-resolved Raman spectroscopy. The fully-symmetric phonon mode shows strongly asymmetric lineshape at low temperature, indicating Fano-type…

It is a matter of current debate whether the gate-tunable superconductivity in twisted bilayer graphene is phonon-mediated or arises from electron-electron interactions. The recent observation of the strong coupling of electrons to…

Superconductivity · Physics 2026-03-20 Glenn Wagner , Yves H. Kwan , Nick Bultinck , Steven H. Simon , S. A. Parameswaran

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

A theoretical investigation of the possible existence of the chiral polaron formation in graphene is reported. We present an analytical method to calculate the ground-state of the electron-phonon system within the framework of the Lee-Low…

Mesoscale and Nanoscale Physics · Physics 2019-07-09 B. S. Kandemir

We report a Raman spectroscopy study of graphene field-effect transistors (GFET) with a controlled amount of defects introduced in graphene by exposure to electron-beam irradiation. Raman spectra are taken at T = 8 K over a range of back…

Materials Science · Physics 2015-06-22 Isaac Childres , Luis A. Jauregui , Yong P. Chen

The magneto-phonon resonance or MPR occurs in semiconductor materials when the energy spacing between Landau levels is continuously tuned to cross the energy of an optical phonon mode. MPRs have been largely explored in bulk semiconductors,…

Materials Science · Physics 2015-06-04 Sarah Goler , Jun Yan , Vittorio Pellegrini , Aron Pinczuk

The equilibrium optical phonons of graphene are well characterized in terms of anharmonicity and electron-phonon interactions, however their non-equilibrium properties in the presence of hot charge carriers are still not fully explored.…

Mesoscale and Nanoscale Physics · Physics 2018-02-15 C. Ferrante , A. Virga , L. Benfatto , M. Martinati , D. De Fazio , U. Sassi , C. Fasolato , A. K. Ott , P. Postorino , D. Yoon , G. Cerullo , F. Mauri , A. C. Ferrari , T. Scopigno

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.…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 L. A. Falkovsky

We investigate the interplay between strong electron correlations and charge-lattice interaction in cuprates. The coupling between half breathing bond stretching phonons and doped holes in the t-t'-J model is studied by limited phonon basis…

Strongly Correlated Electrons · Physics 2015-05-18 G. De Filippis , V. Cataudella , R. Citro , C. A. Perroni , A. S. Mishchenko , N. Nagaosa

We present transport measurements on quantum dots of sizes 45, 60 and 80 nm etched with an Ar/O2-plasma into a single graphene sheet, allowing a size comparison avoiding effects from different graphene flakes. The transport gaps and…

Mesoscale and Nanoscale Physics · Physics 2013-08-01 D. Kölbl , D. M. Zumbühl