相关论文: Electronic Structure, Electron-Phonon Coupling, an…
Recent work on an electron-phonon model in two-dimensions is reviewed and some new results are presented. We utilize both Quantum Monte Carlo simulations and Migdal-Eliashberg theory. The type of electron-ion coupling considered is on-site.…
The attempt to understand cuprate superconductors is complicated by the presence of multiple strong interactions. While many believe that antiferromagnetism is important for the superconductivity, there has been revived interest in the role…
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 discuss the effects of hydrostatic pressure on the superconducting properties of MgB$_{2}$ within the framework of Eliashberg theory. By considering the pressure dependences of all parameters appearing in the McMillan formula, we show…
We report a detailed study of the electronic and structural properties of the 39K superconductor \mgbtwo and of several related systems of the same family, namely \mgalbtwo, \bebtwo, \casitwo and \cabesi. Our calculations, which include…
We present a detailed study on the influence of strong electron-phonon coupling to the photoemission spectra of lead. Representing the strong-coupling regime of superconductivity, the spectra of lead show characteristic features that…
We investigate the dynamical effects of electron-phonon coupling (EPC) on the superconducting properties of two-dimensional (2D) systems, calculating the Eliashberg function in terms of dynamically renormalized phonons. By studying…
Spectral distribution functions of electron-phonon interaction $\alpha^2F(\omega )$ obtained by ab initio linear--response calculations are used to describe various superconducting and transport properties in a number of elemental metals…
This article reviews theoretical and experimental work on the novel physics in multiband superconductors. Multiband superconductors are characterized by multiple superconducting energy gaps in different bands with interaction between Cooper…
We study transport through a double quantum dot system in which each quantum dot is coupled to a phonon mode. Such a system can be realized, e.g., using a suspended carbon nanotube. We find that the interplay between strong electron-phonon…
We study the many-body effects in a two-subband quasi-two-dimensional electron system in a quantizing magnetic field at filling factor three. A manifestation of these effects in the phonon absorption spectroscopy is discussed. The electron…
The electronic structure of electron-doped polycrystalline Mg$_{1-x}$Al$_{x}$(B$_{1-y}$C$_{y}$)$_2$ was examined by electron energy-loss spectroscopy (EELS) in a scanning transmission electron microscope (STEM) and first-principle…
We have calculated the nonlinear current of a number of single band s-wave electron-phonon superconductors. Among issues considered were those of dimensionality, strong electron-phonon coupling, impurities, and comparison with BCS. For the…
Electron-phonon coupling is a key interaction that governs diverse physical processes such as carrier transport, superconductivity, and optical absorption. Calculating such interactions from first-principles with methods beyond…
We present a Raman scattering study of the E2g phonon anharmonicity and of superconductivity induced self-energy effects in MgB2 single crystals. We show that anharmonic two phonon decay is mainly responsible for the unusually large…
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…
Single- and few-layer transition metal dichalcogenides have recently emerged as a new family of layered crystals with great interest, not only from the fundamental point of view, but also because of their potential application in ultrathin…
We present an overview of the measured transport properties of the two dimensional electron fluids in high mobility semiconductor devices with low electron densities, and of some of the theories that have been proposed to account for them.…
Superconducting mechanism mediated by interband exchange Coulomb repulsion is examined in an extended two-band Hubbard models with a wide band crossing the Fermi level and coexisting with a narrower band located at moderately lower energy.…
We review investigations of the electron-phonon interaction (EPI) in metal diborides MeB_2 (Me=Zr, Nb, Ta, Mg) by point-contact (PC) spectroscopy. For transition metal compounds the PC EPI functions were recovered and EPI parameter…