Related papers: Strong phonon softening without Fermi surface nest…
The interaction of electron-hole pairs with lattice vibrations exhibits a wealth of intriguing physical phenomena. The Kohn anomaly is a renowned example where electron-phonon coupling leads to non-analytic phonon dispersion at specific…
Electron-phonon coupling, i.e., the scattering of lattice vibrations by electrons and vice versa, is ubiquitous in solids and can lead to emergent ground states such as superconductivity and charge-density wave order. Strong coupling 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…
The possible occurrence of either a charge-density-wave or a Kohn anomaly is governed by the presence of Fermi-surface nesting and the subtle interaction of electrons and phonons. Recent experimental and theoretical investigations suggest…
We investigate the effect of electron-phonon interaction on the phononic properties in the one-dimensional half-filled Holstein model of spinless fermions. By means of determinantal Quantum Monte Carlo simulation we show that the behavior…
I present the detailed behavior of phonon dispersion curves near momenta which span the electronic Fermi sea in a superconductor. I demonstrate that an anomaly, similar to the metallic Kohn anomaly, exists in a superconductor's dispersion…
The dispersion of electrons and phonons near the K point of bilayer graphene was investigated in a resonant Raman study using different laser excitation energies in the near infrared and visible range. The electronic structure was analyzed…
Electron-phonon interaction in copper oxide superconductors is still enigmatic. Strong coupling for certain optic phonons is now well established experimentally, but theoretical understanding is challenging. Scattering of electrons near the…
The dispersion of phonons in Ba1-xKxBiO3 along the (3+q, 0, 0) direction in reciprocal space was determined for x=0, 0.30, 0.37, 0.52 using high-resolution inelastic X-ray scattering. The observed phonon energies near \Gamma were in good…
Despite extensive investigations, many aspects of charge density waves (CDWs) remain elusive, especially the relative roles of electron-phonon coupling and Fermi surface nesting as the underlying driving mechanisms responsible for the…
In neutral graphene, two prominent cusps known as Kohn anomalies are found in the phonon dispersion of the highest optical phonon at $q=\Gamma$ (LO branch) and $q=K$ (TO branch), reflecting a significant electron-phonon coupling to undoped…
Using high-energy-resolution inelastic x-ray scattering, we observe anomalous softening and damping of the transverse acoustic phonon in UPt$_2$Si$_2$ as the system is cooled towards the charge density wave (CDW) transition temperature,…
The phonon dispersion of graphene on Ir(111) has been determined by means of angle-resolved inelastic electron scattering and density functional calculations. Kohn anomalies of the highest optical-phonon branches are observed at the…
A strong electron-phonon interaction arises from the modulation of the superexchange interaction by phonons. As is studied in Phys. Rev. B 70, 184514 (2004), Cu-O bond stretching modes can be soft around (pm pi/a, 0) and (0, pm pi/a), with…
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…
We report an experimental determination of the dispersion of the soft phonon mode along [1,0,0] in uranium as a function of pressure. The energies of these phonons increase rapidly, with conventional behavior found by 20 GPa, as predicted…
We have investigated the dynamical properties of coherent phonons generated in antimony under high density photo excitation. Precise measurements and extended analysis of coherent phonon oscillations provide new insights into the process of…
We calculate the electronic polarizability in the superconducting state near extremum vectors ${\vec Q}_0$ of the Fermi surface. A pole appears in the polarizability at frequencies $\omega$ near the superconducting gap $2\Delta$ which leads…
Kohn anomalies in three-dimensional metallic crystals are dips in the phonon dispersion that are caused by abrupt changes in the screening of the ion-cores by the surrounding electron-gas. These anomalies are also present at the…
Phonon softening is a ubiquitous phenomenon in condensed matter systems which is often associated with charge density wave (CDW) instabilities and anharmonicity. The interplay between phonon softening, CDW and superconductivity is a topic…