activity
20172022
most citedEfficient evaluation of the polarization function in dynamical mean-field theory

33 citations · 57 across the 3 of their papers we have counts for

collaborators

12 papers

cond-mat.str-el2021

Parametrizations of local vertex corrections from weak to strong coupling: importance of the Hedin three-leg vertex

Viktor Harkov, Alexander I. Lichtenstein, Friedrich Krien

In the study of correlated systems, approximations based on the dynamical mean-field theory (DMFT) provide a practical way to take local vertex corrections into account, which capt…

cond-mat.str-el2020

Fluctuation diagnostic of the nodal/antinodal dichotomy in the Hubbard model at weak coupling: a parquet dual fermion approach

Friedrich Krien, Alexander I. Lichtenstein, Georg Rohringer

We apply the boson exchange parquet solver for dual fermions to the half-filled Hubbard model on a square lattice at small interaction. Our results establish that, in this regime,…

cond-mat.str-el2020

Tiling with triangles: parquet and methods unified

Friedrich Krien, Anna Kauch, Karsten Held

The parquet formalism and Hedin's approach are unified into a single theory of vertex corrections, corresponding to an exact reformulation of the parquet equations in terms o…

cond-mat.str-el2020

Boson-Exchange Parquet Solver for dual fermions

Friedrich Krien, Angelo Valli, Patrick Chalupa +3

We present and implement a parquet approximation within the dual-fermion formalism based on a partial bosonization of the dual vertex function which substantially reduces the compu…

cond-mat.str-el2020

The Bethe-Salpeter equation at the critical end-point of the Mott transition

Erik G. C. P. van Loon, Friedrich Krien, Andrey A. Katanin

Strong repulsive interactions between electrons can lead to a Mott metal-insulator transition. The Dynamical Mean-Field Theory (DMFT) explains the critical end-point and hysteresis…

cond-mat.str-el2019

Parquet-like equations for the Hedin three-leg vertex

Friedrich Krien, Angelo Valli

Taking the competition and the mutual screening of various bosonic fluctuations in correlated electron systems into account requires an unbiased approach to the many-body problem.…