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Related papers: Phonon dispersion and lifetimes in MgB2

200 papers

We use density functional theory to calculate the electronic band structures, cohesive energies, phonon dispersions, and optical absorption spectra of two-dimensional In$_2$X$_2$ crystals, where X is S, Se, or Te. We identify two…

Mesoscale and Nanoscale Physics · Physics 2014-09-19 V. Zolyomi , N. D. Drummond , V. I. Fal'ko

Raman scattering on phonon--plasmon coupled modes in high magnetic fields is considered theoretically. The calculations of the dielectric function were performed in the long-wave approximation for the semiclassical and ultra-quantum…

Materials Science · Physics 2007-05-23 L. A. Falkovsky

We demonstrate how supercell implementations of conventional lattice dynamical calculations can be used to determine the extent and nature of disorder-induced broadening in the phonon dispersion spectrum of disordered crystalline materials.…

Disordered Systems and Neural Networks · Physics 2017-04-26 Alistair R. Overy , Arkadiy Simonov , Philip A. Chater , Matthew G. Tucker , Andrew L. Goodwin

Time-resolved Raman spectroscopy has been applied to probe the anharmonic coupling and electron-phonon interaction of optical phonons in graphite. From the decay of the transient anti-Stokes scattering of the G-mode following ultrafast…

Materials Science · Physics 2015-05-14 Hugen Yan , Daohua Song

The momentum dependent lineshape of the out-of-phase oxygen vibration as measured in recent neutron scattering measurements is investigated. Starting from a microscopic coupling of the phonon vibration to a local crystal field, the phonon…

Superconductivity · Physics 2009-10-31 T. P. Devereaux , A. Virosztek , A. Zawadowski

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

Phonon chirality has attracted intensive attention since it breaks the traditional cognition that phonons are linear propagating bosons. This new quasiparticle property has been extensively studied theoretically and experimentally. However,…

Materials Science · Physics 2021-08-17 Qingan Cai , Olle Hellman , Bin Wei , Qiyang Sun , Ayman H. Said , Thomas Gog , Barry Winn , Chen Li

We measured phonon frequencies and linewidths in doped and undoped BaFe2As2 single crystals by inelastic x-ray scattering and compared our results with density functional theory (DFT) calculations. In agreement with previous work, the…

We investigate phonon lifetimes in VO2 single crystals. We do so in the metallic state above the metal-insulator transition (MIT), where strong structural fluctuations are known to take place. By combining inelastic X-ray scattering and…

Collective excitations of coupled electron-phonon systems are calculated for both monolayer and bilayer graphene, taking into account the non-perturbative Coulomb coupling between electronic excitations in graphene and the substrate…

Mesoscale and Nanoscale Physics · Physics 2010-11-12 E. H. Hwang , Rajdeep Sensarma , S. Das Sarma

The community currently lacks a complete understanding of how resonant inelastic x-ray scattering (RIXS) experiments probe the electron-phonon ($e$-ph) interaction in solids. For example, most theoretical models of this process have focused…

Strongly Correlated Electrons · Physics 2022-05-25 Krzysztof Bieniasz , Steve Johnston , Mona Berciu

In systems having an anisotropic electronic structure, such as the layered materials graphite, graphene and cuprates, impulsive light excitation can coherently stimulate specific bosonic modes, with exotic consequences for the emergent…

We calculate the scattering rates of phonons on two-level systems in disordered trigonal and hexagonal crystals. We apply a model in which the two-level system, characterized by a direction in space, is coupled to the strain field of the…

Disordered Systems and Neural Networks · Physics 2009-11-13 Dragoş-Victor Anghel , Dmitry Churochkin

The temperature dependence below $T_{c}$ of the lineshape of optical phonons of different symmetry as seen in Raman scattering is investigated for superconductors with anisotropic energy gaps. It is shown that the symmetry of the…

Condensed Matter · Physics 2009-10-22 T. P. Devereaux

The electron-phonon interaction and related transport properties are investigated in monolayer silicene and MoS2 by using a density functional theory calculation combined with a full-band Monte Carlo analysis. In the case of silicene, the…

Mesoscale and Nanoscale Physics · Physics 2015-06-12 Xiaodong Li , Jeffrey T. Mullen , Zhenghe Jin , Kostyantyn M. Borysenko , M. Buongiorno Nardelli , Ki Wook Kim

We investigate the low energy acoustical and optical modes in $\mathrm{HgBa_2CuO_{4+\delta}}$ using inelastic x-ray scattering (IXS). The experimental phonon dispersion and the dynamical structure factor are compared with an atomic shell…

Superconductivity · Physics 2009-11-10 Matteo D'Astuto , Alessandro Mirone , Paola Giura , Dorothee Colson , Anne Forget , Michael Krisch

We use a newly developed quantum Monte Carlo method to investigate the impact of finite dispersion of the optical phonon mode on the properties of the bond Su-Schrieffer-Heeger polaron in two dimensions. We compare the properties of the…

Strongly Correlated Electrons · Physics 2024-05-28 Chao Zhang

The effect of high pressures to 40 GPa on the crystal structure and lattice dynamics of AlB2 was studied by synchrotron x-ray powder diffraction, Raman spectroscopy, and first-principles calculations. There are no indications for a…

Superconductivity · Physics 2009-11-07 I. Loa , K. Kunc , K. Syassen , P. Bouvier

We show how the coupling between the phonons and electrons in a strongly correlated metal can result in phonon frequencies which have a non-monotonic temperature dependence. Dynamical mean-field theory is used to study the Hubbard-Holstein…

Strongly Correlated Electrons · Physics 2009-10-31 J. Merino , Ross H. McKenzie

To elucidate the relationship between a crystal's structure, its thermal conductivity, and its phonon dispersion characteristics, an analysis is conducted on layered diatomic Lennard-Jones crystals with various mass ratios. Lattice dynamics…

Materials Science · Physics 2007-05-23 A. J. H. McGaughey , M. I. Hussein , E. S. Landry , M. Kaviany , G. M. Hulbert