Speaker
Johann Ostmeyer
(University of Bonn)
Description
The Fermi-Hubbard model suffers from a severe sign problem, both for non-zero chemical potentials and on non-bipartite lattices. Over the years, considerable progress has been made in alleviating the sign problem by deforming the integration contour of the path integral into the complex plane. In this talk, I am going to present a surprisingly simple and yet powerful contour deformation by means of an optimised constant shift. First results for the molecule Perylene at finite doping are included. I will also discuss preliminary results using fermionic augmented tree tensor networks which are inherently sign problem free.
Author
Johann Ostmeyer
(University of Bonn)
Co-authors
Evan Berkowitz
(Forschungszentrum Jülich)
Christoph Gäntgen
(FZ Jülich)
Stefan Krieg
Thomas Luu
(Forschungszentrum Jülich)
Giovanni Pederiva
(Michigan State University)
Marcel Rodekamp
Manuel Schneider
(Deutsches Elektronen-Synchrotron DESY)
Archil Suladze
(University of Bonn)
Carsten Urbach
(University of Bonn)
