Related papers: Instanton method for the electron propagator
A many-body Green's function approach to the microscopic theory of plasmon-enhanced spectroscopy is presented within the context of localized surface-plasmon resonance spectroscopy and applied to investigate the coupling between…
Instantons present a deep insight into non-perturbative effects both in physics and mathematics. While leading instanton effects can be calculated simply as an exponent of the instanton action, the calculation of subleading contributions…
Capturing non-Markovian dynamics of open quantum systems is generally a challenging problem, especially for strongly-interacting many-body systems. In this work, we combine recently developed non-Markovian quantum state diffusion techniques…
A theory of superconductivity based on the two-body Cooperon propagator is presented. This theory takes the form of a modified Gorkov equation for the Green's function and allows one to model the effect of local superconducting correlations…
We develop a new numerical method to calculate the Landauer conductance through an interacting electron system in the first order perturbation or in the self-consistent Hartree-Fock approximation. It is applied to one and two dimensional…
Electronic quantum entanglement between the central chain and the two electrodes in an infinite one-dimensional two-probe device system is studied. The entanglement entropy is calculated employing the nonequilibrium Green's function method…
The propagator in the instanton background in the $(- \lambda \phi^{4})$ scalar model in four dimensions is studied.Leading and sub-leading terms of its asymptotics for large momenta and its on-shell double residue are calculated…
The one-electron spectral function of the Holstein-Hubbard bipolaron in one dimension is studied using cluster perturbation theory together with the Lanczos method. In contrast to other approaches, this allows one to calculate the spectrum…
Within a quasipotential framework a relativistic analysis is presented of the deuteron current. Assuming that the singularities from the nucleon propagators are important, a so-called equal time approximation of the current is constructed.…
One of the fundamental problems in physics which are not rigorously solved yet is the statistical mechanics of nonequilibrium processes. An important contribution to describe irreversible behavior starting from reversible Hamiltonian…
Uniqueness of effective interaction defined in an extension of the Kohn-Sham theory is proved, if the model with a non-degenerate ground state exists and to reproduce a correlation function as well as the single-particle density of an…
In a recent paper [1] the scattering and transport of excess electrons in liquid argon in the hydrodynamic regime was investigated, generalizing the seminal works of Lekner and Cohen [2,3] with modern scattering theory techniques and…
In a recent series of scanning probe experiments, it became possible to visualize local electron flow in a two-dimensional electron gas. In this paper, a Green's function technique is presented that enables efficient calculation of the…
The non-uniform (or inhomogeneous) electron gas has received much attention in many-body quantum mechanics and quantum chemistry in the early days of density functional theory, mainly as a theoretical device to construct gradient…
I construct a minimal formalism to describe transport of non separable correlations arising when a superconductor is in contact with several electrodes (being ferromagnetic or normal metal). Transport theory is expressed in terms of…
Microscopic calculations of the electromagnetic response of medium-mass nuclei are now feasible thanks to the availability of realistic nuclear interactions with accurate saturation and spectroscopic properties, and the development of…
The method of many-body Green's functions is developed for arbitrary systems of electrons and nuclei starting from the full (beyond Born-Oppenheimer) Hamiltonian of Coulomb interactions and kinetic energies. The theory presented here…
We report the inclusion of electron-electron correlation in the calculation of transport properties within an ab initio scheme. A key step is the reformulation of Landauer's approach in terms of an effective transmittance for the…
The problem of motion of a single electron interacting with a periodic lattice of two-level systems is investigated within a spinless fermion model. The Green's function is calculated in a single-site dynamical coherent potential…
Electronic behavior of a 1D Aubry chain with Hubbard interaction is critically analyzed in presence of electric field. Multiple energy bands are generated as a result of Hubbard correlation and Aubry potential, and, within these bands…