Related papers: Acoustical-Mode-Driven Electron-Phonon Coupling in…
We have investigated the charge dynamics of VO2 by optical reflectivity measurements. Optical conductivity clearly shows a metal-insulator transition. In the metallic phase, a broad Drude-like structure is observed. On the other hand, in…
We investigate metal-insulator transitions in the Holstein-Hubbard model as a function of the on-site electron-electron interaction U and the electron-phonon coupling g. We use several different numerical methods to calculate the phase…
In the layered transition metal oxide LiNbO$_2$ the Nb$^{3+}$ ($4d^2$) ion is trigonal-prismatically coordinated with O ions, with the resulting crystal field leading to a single band system for low energy properties. A tight-binding…
Optically active defects often play a crucial role in governing the light emission as well as the electronic properties of materials. Moreover, defect-mediated states in the mid-gap region can trap electrons, thus opening a path for the…
The search of the phonon structure at the above-gap energies was carried out for $d^{2}V/dI^{2}(V)$ spectra of MgB$_{2}$ point contacts with a normal metal. The two-band model is assumed not only for the gap structure in…
Electronic Raman scattering studies on MgB2 single crystals as a function of excitation and polarization have revealed three distinct superconducting features: a clean gap below 37 cm-1 and two coherence peaks at 109 cm-1 and 78 cm-1 which…
We investigate the influence of electron-phonon coupling on the superexchange interaction of magnetic insulators. Both the Holstein-Hubbard model where the phonons couple to the electron density, as well as an extended Su, Schrieffer,…
We report the first systematic measurements of the Raman scattering by electrons in elemental metals of Al, Mo, Nb, Os, Pb, Re, Ta, Ti, V, W and metallic compound La$B_6$. Experimental spectra are modelled on the base of the band…
Here we have investigated the role of electron-phonon coupling on the Raman spectrum of narrow bandgap semiconductors APd3O4 (A = Ca, Sr) and hole-doped system Sr0.85Li0.15Pd3O4. Four Raman active phonons are observed at room temperature…
Using electronic structure calculation we study the superconducting properties of the theoretically-devised superconductor MS1-LiB (LiB). We calculate the electron-phonon coupling ($\lambda=0.62$) and the phonon frequency logarithmic…
We present a theoretical description of the coupling between longitudinal optical phonons and collective excitations of a two-dimensional electron gas. By diagonalizing the Hamiltonian of the system, including Coulomb electron-electron and…
Ta2NiSe5 is considered a promising excitonic insulator (EI) candidate with slight phonon contributions, since it exhibits a tiny orthorhombic-to-monoclinic structural distortion at 328 K without any superlattice structure. Our synchrotron…
We reexamine the putative Peierls transition in a (5,5) metallic nanotube. We show that the conduction electrons at the Fermi level do not couple to the longitudinal acoustic phonon but rather to a folded-in graphene zone edge phonon having…
The unusual Raman spectrum of MgB$_2$ and its formidable temperature dependence are successfully reproduced by means of a parameter-free \emph{ab initio} nonadiabatic theory that accounts for the electron-hole pair scattering mechanisms…
The polaron features for long-range electron-phonon interaction are investigated by extending a variational approach previously proposed for the study of systems with local coupling. The ground-state spectral weight, the average kinetic…
We present electronic structure calculations, electrical resistivity data and the first specific heat measurements in the normal and superconducting states of quasi-one-dimensional M2Mo6Se6 (M = Tl, In, Rb). Rb2Mo6Se6 undergoes a…
Renormalization of the electronic band gap due to electron-phonon coupling in the tetrahedral semiconductors diamond, silicon and cubic silicon carbide is studied from first principles. There is a marked difference between the coupling of…
The adiabatic Born-Oppenheimer approximation is considered to be a robust approach that very rarely breaks down. Consequently, it is predominantly utilized to address various electron-phonon properties in condensed matter physics. By…
The large van der Waals gap in transition metal dichalcogenides (TMDs) offers an avenue to host external metal atoms that modify the ground state of these 2D materials. Here, we experimentally and theoretically address the charge…
The search for intrinsic excitonic insulators (EI) has long been confounded by coexisting electron-phonon coupling in bulk materials. Although the ground state of an EI may be difficult to differentiate from density-wave orders or other…