4 papers
Instabilities in self-consistent diagrammatic approaches and how to cure them
Marcel Gievers, Herbert Eßl, Stefan Rohshap +2
While self-consistent diagrammatic approaches are widely used to compute the physical properties of correlated quantum materials, their applicability may get severely hindered prec…
On Degeneracies of Density, Magnetic, and Pairing Responses: How Competing Orders Echo Underlying Symmetries in the Hubbard Model
Michael Meixner, Herbert Eßl, Matthias Reitner +2
Strongly correlated electron systems often display competing or even intertwined ordering tendencies, hinting to extremely close or degenerate many-electron energies. While degener…
Stabilizing the parquet problem
Herbert Eßl, Stefan Rohshap, Marcel Gievers +3
We systematically analyze the stability of the iterative solution of the parquet equations by studying the spectrum of the Jacobian associated with the commonly used damped fixed-p…
Origin of misleading convergence in self-consistent many-electron theories: Fundamental aspects and practical implications
Herbert Eßl, Matthias Reitner, Evgeny Kozik +1
Self-consistent approaches in many-electron problems typically converge to an unphysical solution in strongly correlated regimes. By deriving the mathematical condition for the sta…