Variational matrix-product-state approach to quantum impurity models

Autor(en)

Andreas Weichselbaum, Frank Verstraete, Ulrich Schollwöck, J. Ignacio Cirac, Jan von Delft

Abstrakt

We present a unified framework for renormalization group methods, including Wilson’s numerical renormalization group (NRG), and White’s density-matrix renormalization group (DMRG), within the language of matrix-product-states. This allows improvements over Wilson’s NRG for quantum impurity models, as we illustrate for the one-channel Kondo model. Moreover, we use a variational method for evaluating Green’s functions. The proposed method is more flexible in its description of spectral properties at finite frequencies, opening the way to time-dependent, out-of-equilibrium impurity problems. It also substantially improves computational efficiency for one-channel impurity problems, suggesting potentially linear scaling of complexity for n-channel problems.

Organisation(en)

Quantenoptik, Quantennanophysik und Quanteninformation

Externe Organisation(en)

Ludwig-Maximilians-Universität München, Rheinisch-Westfälische Technische Hochschule Aachen, Max-Planck-Institut für Quantenoptik

Journal

Physical Review B

Band

80

Anzahl der Seiten

7

ISSN

1098-0121

DOI

https://doi.org/10.1103/PhysRevB.80.165117

Publikationsdatum

10-2009

Peer-reviewed

Ja

ÖFOS 2012

103025 Quantenmechanik

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/3ee33b29-922e-48e8-a74f-8f44ddc8fff4