Efficient DMFT impurity solver using real-time dynamics with matrix product states

Autor(en)

Martin Ganahl, Markus Aichhorn, Hans Gerd Evertz, Patrik Thunstroem, Karsten Held, Frank Verstraete

Abstrakt

We propose to calculate spectral functions of quantum impurity models using the time evolving block decimation (TEBD) for matrix product states. The resolution of the spectral function is improved by a so-called linear prediction approach. We apply the method as an impurity solver within the dynamical mean-field theory (DMFT) for the single-and two-band Hubbard model on the Bethe lattice. For the single-band model, we observe sharp features at the inner edges of the Hubbard bands. A finite-size scaling shows that they remain present in the thermodynamic limit. We analyze the real time-dependence of the double occupation after adding a single electron and observe oscillations at the same energy as the sharp feature in the Hubbard band, indicating a long-lived coherent superposition of states that correspond to the Kondo peak and the side peaks. For a two-band Hubbard model, we observe an even richer structure in the Hubbard bands, which cannot be related to a multiplet structure of the impurity, in addition to sharp excitations at the band edges of a type similar to the single-band case.

Organisation(en)

Quantenoptik, Quantennanophysik und Quanteninformation

Externe Organisation(en)

Technische Universität Graz, Perimeter Institute for Theoretical Physics, Technische Universität Wien, Ghent University

Journal

Physical Review B

Band

92

Anzahl der Seiten

12

ISSN

1098-0121

DOI

https://doi.org/10.1103/PhysRevB.92.155132

Publikationsdatum

10-2015

Peer-reviewed

Ja

ÖFOS 2012

103015 Kondensierte Materie

Schlagwörter

ASJC Scopus Sachgebiete

Electronic, Optical and Magnetic Materials, Condensed Matter Physics

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/a2ebdfa4-d3e8-4660-b1e4-8cc5db65722e