158 citations · 777 across the 35 of their papers we have counts for
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Algebraic Diagrammatic Construction of the Multichannel Dyson Equation
Thibault Demartini, J. Arjan Berger, Guillaume Blanchon +4
The multichannel Dyson equation (MCDE) was recently introduced as a new approximation scheme to compute the one-body Green function in many-body systems, as reported by Riva et al.…
The multichannel Dyson equation for double ionisation spectroscopies
Pierre Sellié, J. Arjan Berger, Pina Romaniello
Several photoemission spectroscopies and, in particular, Auger spectroscopy, involve double-ionization processes. For the numerical simulation of these spectroscopies it is conveni…
Ground and excited-state properties of the extended Hubbard dimer from the multichannel Dyson equation
Stefano Paggi, J. Arjan Berger, Pina Romaniello
We have recently presented the multichannel Dyson equation as an alternative to the standard single-channel Dyson equation. While the latter involves a single many-body Green's fun…
Multichannel Dyson equations for even- and odd-order Green's functions: application to double excitations
Gabriele Riva, Théodore Fischer, Stefano Paggi +2
We extend the concept of the multichannel Dyson equation that we have recently derived to model photoemission spectra by coupling the one- and the three-body Green's functions, to…
The multi-channel Dyson equation: coupling many-body Green's functions
Gabriele Riva, Pina Romaniello, J. Arjan Berger
We present the multi-channel Dyson equation that combines two or more many-body Green's functions to describe the electronic structure of materials. In this work we use it to model…
Screened extended Koopmans' theorem: photoemission at weak and strong correlation
S. Di Sabatino, J. Koskelo, J. A. Berger +1
By introducing electron screening in the extended Koopmans' theorem we correctly describe the band gap opening in weakly as well as strongly correlated systems. We show this by app…
Introducing screening in one-body density matrix functionals: impact on the Extended Koopmans' Theorem's charged excitations of model systems
S. Di Sabatino, J. Koskelo, J. A. Berger +1
In this work we get insight into the impact of reduced density matrix functionals on the quality of removal/addition energies obtained using the Extended Koopmans' Theorem (EKT). W…
Photoemission spectral functions from the three-body Green's function
Gabriele Riva, Timothée Audinet, Matthieu Vladaj +2
We present an original strategy for the calculation of direct and inverse photo-emission spectra from first principles. The main goal is to go beyond the standard Green's function…
Photoemission spectra from the Extended Koopman's Theorem, revisited
S. Di Sabatino, J. Koskelo, J. Prodhon +3
The Extended Koopman's Theorem (EKT) provides a straightforward way to compute charged excitations from any level of theory. In this work we make the link with the many-body effect…
Many-Body Effective Energy Theory: photoemission at strong correlation
S. Di Sabatino, J. A. Berger, P. Romaniello
In this work we explore the performance of a recently derived many-body effective energy theory for the calculation of photoemission spectra in the regime of strong electron correl…
Many-body perturbation theory and non-perturbative approaches: the screened interaction as key ingredient
Walter Tarantino, Bernardo S. Mendoza, Pina Romaniello +2
Many-body perturbation theory is often formulated in terms of an expansion in the dressed instead of the bare Green's function, and in the screened instead of the bare Coulomb inte…
The self-consistent Dyson equation and self-energy functionals: failure or new opportunities?
Walter Tarantino, Pina Romaniello, J. A. Berger +1
Perturbation theory using self-consistent Green's functions is one of the most widely used approaches to study many-body effects in condensed matter. On the basis of general consid…
Photoemission Spectra from Reduced Density Matrices: the Band Gap in Strongly Correlated Systems
Stefano Di Sabatino, J. A. Berger, Lucia Reining +1
We present a method for the calculation of photoemission spectra in terms of reduced density matrices. We start from the spectral representation of the one-body Green's function G,…
Reduced Density-Matrix Functional Theory: correlation and spectroscopy
Stefano Di Sabatino, Jan A. Berger, Lucia Reining +1
In this work we explore the performance of approximations to electron correlation in reduced density-matrix functional theory (RDMFT) and of approximations to the observables calcu…
Beyond the GW approximation: combining correlation channels
Pina Romaniello, Friedhelm Bechstedt, Lucia Reining
In many-body perturbation theory (MBPT) the self-energy Σ=iGWΓplays the key role since it contains all the many body effects of the system. The exact self-energy is not known; as f…
The valence electron photoemission spectrum of semiconductors: ab initio description of multiple satellites
Matteo Guzzo, Giovanna Lani, Francesco Sottile +7
The experimental valence band photoemission spectrum of semiconductors exhibits multiple satellites that cannot be described by the GW approximation for the self-energy in the fram…
Approximations for many-body Green's functions: insights from the fundamental equations
Giovanna Lani, Pina Romaniello, Lucia Reining
Several widely used methods for the calculation of band structures and photo emission spectra, such as the GW approximation, rely on Many-Body Perturbation Theory. They can be obta…