Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe

TT: Fachverband Tiefe Temperaturen

TT 20: Correlated Electrons - Poster Session

TT 20.19: Poster

Mittwoch, 28. März 2007, 14:00–17:45, Poster A

Matrix Product States for comparing NRG to DMRG — •Hamed Saberi, Andreas Weichselbaum, and Jan von Delft — Arnold Sommerfeld Center for Theoretical Physics and Center for NanoScience, Ludwig-Maximilians-Universität, Munich, Germany

Wilson's Numerical Renormalization Group (NRG) method for solving quantum impurity models can be turned into a variational method within the set of so-called Matrix Product States (MPS) with much more flexibility and efficient use of numerical resources. Since White's Density Matrix Renormalization Group (DMRG) for treating quantum lattice problems can likewise be reformulated in terms of MPSs, the NRG and DMRG are now seen to have the same formal basis, namely both are built on MPS. This enables us to compare the NRG approach for the Single Impurity Anderson model to the DMRG approach and also to see how NRG results can be improved upon systematically by performing a variational optimization in a space of variational matrix product states of the same structure as those used by NRG.