English
Related papers

Related papers: Truncation method for Green's functions in time-de…

200 papers

We derive formal expressions of time-dependent energy and heat currents through a nanoscopic device using the Keldysh nonequilibrium Green function technique. Numerical results are reported for a metal/dot/metal junction where the dot level…

Mesoscale and Nanoscale Physics · Physics 2012-05-16 Adeline Crépieux , Fedor Simkovic , Benjamin Cambon , Fabienne Michelini

We introduce a general scheme to consistently truncate equations of motion for Green's functions. Our scheme is guaranteed to generate physical Green's functions with real excitation energies and positive spectral weights. There are free…

Strongly Correlated Electrons · Physics 2021-02-24 Francesco Catalano , Johan Nilsson

We present a theoretical framework to describe experiments directed to controlling single-atom spin dynamics by electrical means using a scanning tunneling microscope. We propose a simple model consisting of a quantum impurity connected to…

Mesoscale and Nanoscale Physics · Physics 2022-01-25 Jose Reina-Gálvez , Nicolás Lorente , Fernando Delgado , Liliana Arrachea

This paper is concerned with the problem of an acoustic wave scattering in a locally perturbed periodic structure. As the total wavefield is non-quasi-periodic, effective truncation techniques are pursued for high-accuracy numerical…

Numerical Analysis · Mathematics 2025-12-16 Wangtao Lu , Kuanrong Shen , Ruming Zhang

Sub-wavelength arrays of quantum emitters offer an efficient free-space approach to coherent light-matter interfacing, using ultracold atoms or two-dimensional solid-state quantum materials. The combination of collectively suppressed…

Quantum Gases · Physics 2024-12-16 Simon Panyella Pedersen , Georg M. Bruun , Thomas Pohl

The exact nonlinear response of noninteracting (Bloch) electrons is examined within a nonequilibrium formalism on the infinite-dimensional hypercubic lattice. We examine the effects of a spatially uniform, but time-varying electric field…

Statistical Mechanics · Physics 2009-11-10 V. Turkowski , J. K. Freericks

We present a numerically efficient technique to evaluate the Green's function for extended two dimensional systems without relying on periodic boundary conditions. Different regions of interest, or `patches', are connected using self energy…

Mesoscale and Nanoscale Physics · Physics 2015-06-23 Mikkel Settnes , Stephen R. Power , Jun Lin , Dirch H. Petersen , Antti-Pekka Jauho

We present an implementation of the steady state Keldysh approach in a Green's function multiple scattering scheme to calculate the non-equilibrium spin density. This density is used to obtain the spin transfer torque in junctions showing…

Mesoscale and Nanoscale Physics · Physics 2008-02-13 Christian Heiliger , Michael Czerner , Bogdan Yu. Yavorsky , Ingrid Mertig , Mark D. Stiles

In Green's function theory, the total energy of an interacting many-electron system can be expressed in a variational form using the Klein or Luttinger-Ward functionals. Green's function theory also naturally addresses the case where the…

Materials Science · Physics 2025-08-26 Andrea Ferretti , Tommaso Chiarotti , Nicola Marzari

We have developed a Green's function formalism based on the use of an overcomplete semicoherent basis of vortex states, specially devoted to the study of the Hamiltonian quantum dynamics of electrons at high magnetic fields and in an…

Mesoscale and Nanoscale Physics · Physics 2009-09-21 T. Champel , S. Florens

A theoretical description of quantum mechanical steady states is developed. Applications for simple quantum mechanical systems described in terms of coupled level structures yield a formulation equivalent to time independent scattering…

Condensed Matter · Physics 2009-11-07 D. Segal , A. Nitzan

We report on the passive measurement of time-dependent Green's functions in the optical frequency domain with low-coherence interferometry. Inspired by previous studies in acoustics and seismology, we show how the correlations of a…

Here we address two nonequilibrium Green's functions approaches for a resonant tunneling structure under a sudden switch of a bias. Our aim is to stress that the time-dependent Keldysh formulation of Jauho, Wingreen and Meir, and the…

Mesoscale and Nanoscale Physics · Physics 2017-03-08 Mariana M. Odashima , Caio H. Lewenkopf

The basic mathematical properties of Green's functions used in statistical mechanics as well as the equations defining these functions and the techniques of solving these equations are reviewed. An approach is presented called the…

Statistical Mechanics · Physics 2007-05-23 V. I. Yukalov

The transport and gain properties of quantum cascade (QC) structures are investigated using a nonequilibrium Green's function (NGF) theory which includes quantum effects beyond a Boltzmann transport description. In the NGF theory, we…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 S. -C. Lee , A. Wacker

An ensemble Green's function formalism, based on the von Neumann density matrix approach, to calculate one-electron excitation spectra of a many-electron system with degenerate ground states is proposed. A set of iterative equations for the…

Strongly Correlated Electrons · Physics 2019-12-24 Erik Linnér , Ferdi Aryasetiawan

We present a numerically efficient and accurate Multiple Scattering formalism, which is a generalization of the Multiple Scattering method with a truncated basis set [X. -G. Zhang and W. H. Butler, Phys. Rev. B 46,7433 (1992)]. Compared to…

Quantum Physics · Physics 2016-05-03 Junqing Xu , Keisuke Hatada , Didier Sébilleau , Li Song

Closed expression for the Green's function of the stationary two-dimensional Schrodinger equation for an electron in group-VI dichalcogenides in the presence of a magnetic field is obtained in terms of the Whittaker functions. The resulting…

Mesoscale and Nanoscale Physics · Physics 2016-12-14 Tomasz M Rusin , Wlodek Zawadzki

We calculate the Green's functions for the particle-vortex system, for two anyons on a plane with and without a harmonic regulator and in a uniform magnetic field. These Green's functions which describe scattering or bound states (depending…

Quantum Physics · Physics 2007-05-23 P. F. Borges , H. Boschi-Filho , A. N. Vaidya

The charge transport of a serially coupled quantum dots (SCQD) connected to the metallic electrodes is theoretically investigated in the Coulomb blockade regime. A closed-form expression for the tunneling current of SCQD in the {\color{red}…

Mesoscale and Nanoscale Physics · Physics 2015-05-27 David M. -T. Kuo , Shiue-Yuan , Yia-chung Chang