H. Hafermann, S. Brener, A. N. Rubtsov, M. I. Katsnel'son, A. I. Lichtenstein, “Cluster Dual Fermion Approach to Nonlocal Correlations”, Письма в ЖЭТФ, 2007, том 86, выпуск 10,страницы 769

Эта публикация цитируется в 37 статьях

КОНДЕНСИРОВАННЫЕ СРЕДЫ

Cluster Dual Fermion Approach to Nonlocal Correlations

H. Hafermann^a, S. Brener^a, A. N. Rubtsov^b, M. I. Katsnel'son^c, A. I. Lichtenstein^a

^a Institute of Theoretical Physics, University of Hamburg, 20355 Hamburg, Germany
^b Department of Physics, Moscow State University
^c Institute for Molecules and Materials, Radboud University, 6525 ED Nijmegen, The Netherlands

Аннотация: We formulate a general cluster Dual Fermion Approach to nonlocal correlations in crystals. The scheme allows the treatment of long-range correlations beyond the cluster DMFT and nonlocal effects in realistic calculations of multiorbital systems. We show that the simplest approximation exactly corresponds to the freecluster DMFT. We apply this approach to the one-dimensional Hubbard model. Already the first dual-fermion correction to the free cluster leads to a drastic improvement of the calculated Green function.

PACS: 71.10.Fd, 71.15.-m, 71.27.+a

Поступила в редакцию: 13.09.2007
Исправленный вариант: 18.10.2007

Язык публикации: английский