6 papers
Dynamical scaling near the pseudogap quantum critical point of the two-dimensional Hubbard model
Mathias Pelz, Gabriel Kotliar, Jan von Delft +1
We study dynamical scaling in the quantum-critical fan of the pseudogap-metal to Fermi-liquid transition of the two-dimensional Hubbard model. Using a four-patch dynamical cluster…
Quantum criticality in the two-dimensional Hubbard model
Mathias Pelz, Gabriel Kotliar, Jan von Delft +1
We study the normal-state, doping-driven phase diagram of the square-lattice Hubbard model using the dynamical cluster approximation combined with the numerical renormalization gro…
Symmetric estimator for discrete self-energy of discrete many-body systems
Aleksandrs Zacinskis, Frank T. Ebel, Mathias Pelz +5
We derive a discrete spectral representation of the single-particle self-energy using a discrete evaluation of Kugler's symmetric improved estimator. Our construction can be used o…
Liouvillian interpolation of the self-energy of cluster dynamical mean-field theories
Mathias Pelz, Jan von Delft, Andreas Gleis
Two widely-used non-local extensions of dynamical mean field theory (DMFT), cellular DMFT (CDMFT) and the dynamical cluster approximation (DCA), both yield self-energies marred by…
Compressing local vertex functions from the multipoint numerical renormalization group using quantics tensor cross interpolation
Markus Frankenbach, Marc Ritter, Mathias Pelz +3
The multipoint numerical renormalization group (mpNRG) is a powerful impurity solver that provides accurate spectral data useful for computing local, dynamic correlation functions…
Testing the parquet equations and the U(1) Ward identity for real-frequency correlation functions from the multipoint numerical renormalization group
Nepomuk Ritz, Anxiang Ge, Markus Frankenbach +3
Recently, it has become possible to compute real-frequency four-point correlation functions of quantum impurity models using a multipoint extension of the numerical renormalization…