Related papers: Antiadiabatic Phonons and Superconductivity in Eli…
This work investigates amplitude-dependent nonlinear corrections to the dissipative conductivity in superconductors, using the Keldysh--Usadel theory of nonequilibrium superconductivity, which captures the nonequilibrium dynamics of both…
We discuss the limits and the correct utilization of the standard program for the inversion of Eliashberg equations and the determination of the electron-phonon spectral function and the coulomb pseudopotential from tunneling measurements…
We investigate the applicability of Migdal--Eliashberg (ME) theory by revisiting Migdal's analysis within the dynamical mean-field theory framework. First, we compute spectral functions, the quasi-particle weight, the self energy,…
We use the dynamical mean-field method to calculate the charge density wave transition temperature of the half-filled Holstein model as function of typical phonon frequency in the physically relevant adiabatic limit of phonon frequency…
A recent experiment by Shimizu et al. has provided evidence of a superconducting phase in hcp Fe under pressure. To study the pressure-dependence of this superconducting phase we have calculated the phonon frequencies and the…
Superconductivity of doped SrTiO3 is proven to be a particular case of the broader concept of the non-adiabatic pairing mediated by phonons with frequency comparable or larger the Fermi energy. We argue that, for carrier concentrations…
A high order series expansion is employed to study the thermodynamical properties of a S=1/2 chain coupled to dispersionless phonons. The results are obtained without truncating the phonon subspace since the series expansion is performed…
The theory of electron-phonon superconductivity depends on retardation drastically reducing effects of the strong Coulomb repulsion. The standard theory only treats the lowest order diagram, which is an uncontrolled approximation. We study…
The Allen-Heine-Cardona theory allows us to calculate phonon-induced electron self-energies from first principles without resorting to the adiabatic approximation. However, this theory has not been able to account for the change of the…
It is shown on the basis of the multiplicative renormalization-group method of two-loop order that the low-energy effective Hamiltonian of a strongly coupled local electron-phonon system is mapped to the two-channel Kondo model. A phonon is…
Eliashberg theory (ET) generalized for the account of the peculiar properties of the finite zone width electron-phonon (EP) systems with the non constant electron density of states, the electron-hole nonequivalence, chemical potential…
We present a method for solving impurity models with electron-phonon coupling, which treats the phonons efficiently and without approximations. The algorithm is applied to the Holstein-Hubbard model in the dynamical mean field…
In this work we study the effects of nonadiabatic external driving on the thermodynamics of an electronic system coupled to two electronic leads and to a phonon mode, with and without damping. In the limit of slow driving, we establish…
We formulate and solve the Eliashberg equations on the imaginary frequency axis at temperatures below $T_c$ in the weak-coupling limit. We find an excellent scaling at all temperatures, for a given coupling strength, and the normalized…
It is widely believed that in an adiabatic limit a Fermi liquid state of an electron-phonon system described by Migdal-Eliashberg theory remains stable before a dressed phonon softens. Using Holstein model as a prototypical example and…
Recently, band-off-diagonal superconductivity has been proposed [Nat. Commun. 14, 7134 (2023)] as a candidate pairing state for twisted graphene systems. Based on mean-field theory, it was shown that it not only naturally emerges from both…
The electronic structure, phonons, electron-phonon coupling, and superconductivity are theoretically studied in noncentrosymmetric superconductor ThCoC$_2$ as a function of pressure, in the pressure range 0 - 20 GPa. We found that the…
The electronic properties of correlated metals with a strong electron-phonon coupling may be understood in terms of a combination of Landau's Fermi-liquid theory and the strong-coupling theory of Migdal and Eliashberg. In these lecture…
In conventional \textit{ab initio} methodologies, phonons are calculated by solving equations of motion involving static interatomic force constants and atomic masses. The Born-Oppenheimer approximation, where all electronic degrees of…
Lortz et al. [Phys. Rev. B 73, 024512 (2006)] have utilized specific heat and resistivity measurements as "thermal spectroscopies" to deconvolve the spectrum of the electron-phonon interaction in YB$_6$ assuming a major role of the low…