48 citations · 150 across the 8 of their papers we have counts for
8 papers
Short-range excitonic phenomena in low-density metals
Jaakko Koskelo, Lucia Reining, Matteo Gatti
Excitonic effects in metals are commonly supposed to be weak, because the Coulomb interaction is strongly screened. We investigate the low-density regime of the homogeneous electro…
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 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…
Photoemission spectrum in paramagnetic FeO under pressure: towards an \textit{ab-initio} description
S. Di Sabatino, J. Koskelo, J. A. Berger +1
In this work we provide an exhaustive study of the photemission spectrum of paramagnetic FeO under pressure using a refined version of our recently derived many-body effective ener…
Excitons in van der Waals materials: from monolayer to bulk hexagonal boron nitride
Jaakko Koskelo, Giorgia Fugallo, Mikko Hakala +3
We present a general picture of the exciton properties of layered materials in terms of the excitations of their single-layer building blocks. To this end, we derive a model excito…