307 citations · 996 across the 26 of their papers we have counts for
8 papers · 1 filter
Novel approaches to spectral properties of correlated electron materials: From generalized Kohn-Sham theory to screened exchange dynamical mean field theory
Pascal Delange, Steffen Backes, Ambroise van Roekeghem +3
The most intriguing properties of emergent materials are typically consequences of highly correlated quantum states of their electronic degrees of freedom. Describing those materia…
Hubbard interactions in iron-based pnictides and chalcogenides: Slater parametrization, screening channels and frequency dependence
Ambroise van Roekeghem, Loïg Vaugier, Hong Jiang +1
We calculate the strength of the frequency-dependent on-site electronic interactions in the iron pnictides LaFeAsO, BaFe2As2, BaRu2As2, and LiFeAs and the chalcogenide FeSe from fi…
Electronic Polarons, Cumulants and Doubly Dynamical Mean Field Theory: Theoretical Spectroscopy for Correlated and Less Correlated Materials
Silke Biermann, Ambroise van Roekeghem
The use of effective local Coulomb interactions that are dynamical, that is, frequency-dependent, is an efficient tool to describe the effect of long-range Coulomb interactions and…
Spectral properties of transition metal pnictides and chalcogenides: angle-resolved photoemission spectroscopy and dynamical mean field theory
Ambroise van Roekeghem, Pierre Richard, Hong Ding +1
Electronic Coulomb correlations lead to characteristic signatures in the spectroscopy of transition metal pnictides and chalcogenides: quasi-particle renormalizations, lifetime eff…
Towards a first-principles determination of effective Coulomb interactions in correlated electron materials: Role of intershell interactions
Priyanka Seth, Philipp Hansmann, Ambroise van Roekeghem +2
The determination of the effective Coulomb interactions to be used in low-energy Hamiltonians for materials with strong electronic correlations remains one of the bottlenecks for p…
Tetragonal and collapsed-tetragonal phases of CaFe2As2 -- a view from angle-resolved photoemission and dynamical mean field theory
Ambroise van Roekeghem, Pierre Richard, Xun Shi +8
We present a study of the tetragonal to collapsed-tetragonal transition of CaFe2As2 using angle-resolved photoemission experiments and dynamical mean field theory-based electronic…
Screened exchange dynamical mean field theory and its relation to density functional theory: SrVO3 and SrTiO3
Ambroise van Roekeghem, Silke Biermann
We present the first application of a recently proposed electronic-structure scheme to transition metal oxides: screened exchange dynamical mean-field theory includes non-local exc…
Dynamical correlations and screened exchange on the experimental bench: spectral properties of the cobalt pnictide BaCo2As2
Ambroise van Roekeghem, Thomas Ayral, Jan M. Tomczak +7
Understanding the Fermi surface and low-energy excitations of iron or cobalt pnictides is crucial for assessing electronic instabilities such as magnetic or superconducting states.…