Related papers: Nonadiabatic coupling effects in MgB$_2$ reexamine…
The phonon density-of-states of transition metal diborides TMB2 with TM = Ti, V, Ta, Nb and Y has been measured using the technique of inelastic neutron scattering. The experimental data are compared with ab initio density functional…
We present studies of the photoexcited quasiparticle dynamics in MgB2 where, using femtosecond optical techniques, Cooper pair breaking dynamics (PBD) have been temporally resolved for the first time. The PBD are strongly temperature and…
A theory for electronic Raman scattering in the cuprate superconductors is presented with a specific emphasis on the polarization dependence of the spectra which can infer the symmetry of the energy gap. Signatures of the effects of…
The phonon-mode decomposition of the electron-phonon coupling in the MgB2-like system Li_{1-x}BC is explored using first principles calculations. It is found that the high temperature superconductivity of such systems results from extremely…
Elucidating the details of the electron-phonon coupling in semiconductors and insulators is a topic of pivotal interest, as it governs the transport mechanisms and is responsible for various phenomena such as spectral-weight transfers to…
The temperature and magnetic field dependence of lattice and carrier excitations in MnSi is studied in detail using inelastic light scattering. The pure symmetry components of the electronic response are derived from the polarization…
We present a Raman scattering study of Ca$_2$RuO$_4$, in which we investigate the temperature-dependence of the lattice dynamics and the electron-phonon interaction below the metal-insulator transition temperature ({\it T}$_{\rm MI}$).…
Nonadiabatic ring-polymer molecular dynamics employs the mapping approach to describe nonadiabatic effects within the ring-polymer ansatz. In this paper, it is generalized to allow for the nuclear and electronic degrees of freedom to be…
Coupling between electrons and phonons (lattice vibrations) drives the formation of the electron pairs responsible for conventional superconductivity. The lack of direct evidence for electron-phonon coupling in the electron dynamics of the…
We report Raman spectra and synchrotron x-ray diffraction measurements of lattice parameters of polycrystalline MgB2 under hydrostatic pressure conditions up to 15 GPa. An anomalously broadened Raman band at 620 cm-1 is observed that…
Raman scattering in the three-dimensional Dirac semimetal Cd3As2 shows an intricate interplay of electronic and phonon degrees of freedom. We observe resonant phonon scattering due to interband transitions, an anomalous anharmonicity of…
Including the effect of lattice anharmonicity on electron-phonon interactions has recently garnered attention due to its role as a necessary and significant component in explaining various phenomena, including superconductivity, optical…
Electron transfer is an important and fundamental process in chemistry, biology and physics, and has received significant attention in recent years. Perhaps one of the most intriguing questions concerns with the realization of the…
Using the Eliashberg theory of superconductivity we have examined several properties of a model in which electrons are coupled only to rattling phonon modes represented by a sharp peak in the electron-phonon coupling function. Our choice of…
We report plane-polarized Raman scattering spectra of iron oxypnictide superconductor NdFeAsO$_{1-x}$F$_x$ single crystals with varying fluorine $x$ content. The spectra exhibit sharp and symmetrical phonon lines with a weak dependence on…
Surface enhanced Raman spectra from molecules (bipyridyl ethylene) adsorbed on gold dumbells are observed to become increasingly asymmetric (Fano-like) at higher incident light intensity. The electronic temperature (inferred from the…
The BCS electron-phonon mechanism and the unconventional 'hole mechanism' have been proposed as explanations for the high temperature superconductivity observed in $MgB_2$. It is proposed that a critical test of which theory is correct is…
We consider the nonadiabatic energy fluctuations of a many-body system in a time-dependent harmonic trap. In the presence of scale-invariance, the dynamics becomes self-similar and the nondiabatic energy fluctuations can be found in terms…
The optical properties of polarons are studied in the framework of the Holstein model by applying the dynamical mean-field theory. This approach allows to enlighten important quantitative and qualitative deviations from the limiting…
We report on measurements of the specific heat of the recently discovered superconductor MgB$_2$ in the temperature range between 3 and 220 K. Based on a modified Debye-Einstein model, we have achieved a rather accurate account of the…