Description: Massively parallel simulations of strong electronic correlations: Realistic Coulomb vertex and multiplet effects

This title appears in the Scientific Report : 2017

Massively parallel simulations of strong electronic correlations: Realistic Coulomb vertex and multiplet effects

We discuss the efficient implementation of general impurity solvers for dynamical mean-field theory. We show that both Lanczos and quantum Monte Carlo in different flavors (Hirsch-Fye, continuous-time hybridization- and interaction-expansion) exhibit excellent scaling on massively parallel supercomp...

Personal Name(s):	Baumgärtel, M.
	Ghanem, K. / Kiani, A. / Koch, E. / Pavarini, E. (Corresponding author) / Sims, H. / Zhang, G.
Contributing Institute:	Jülich Supercomputing Center; JSC Theoretische Nanoelektronik; IAS-3
Published in:	European physical journal special topics, 226 (2017) 11, S. 2525 - 2547
Imprint:	Berlin Springer 2017
DOI:	10.1140/epjst/e2016-60311-8
Document Type:	Journal Article
Research Program:	AICES Aachen Institute for Advanced Study in Computational Engineering Science Computational Science and Mathematical Methods Controlling Collective States
Link:	OpenAccess
	Publikationsportal JuSER

Please use the identifier: http://dx.doi.org/10.1140/epjst/e2016-60311-8 in citations.
Please use the identifier: http://hdl.handle.net/2128/14942 in citations.

We discuss the efficient implementation of general impurity solvers for dynamical mean-field theory. We show that both Lanczos and quantum Monte Carlo in different flavors (Hirsch-Fye, continuous-time hybridization- and interaction-expansion) exhibit excellent scaling on massively parallel supercomputers. We apply these algorithms to simulate realistic model Hamiltonians including the full Coulomb vertex, crystal-field splitting, and spin-orbit interaction. We discuss how to remove the sign problem in the presence of non-diagonal crystal-field and hybridization matrices. We show how to extract the physically observable quantities from imaginary time data, in particular correlation functions and susceptibilities. Finally, we present benchmarks and applications for representative correlated systems.