%0 Journal Article
%T Interplay between Point-Group Symmetries and the Choice of the Bloch Basis in Multiband Models
%A Stefan A. Maier
%A Carsten Honerkamp
%A Qiang-Hua Wang
%J Symmetry
%D 2013
%I MDPI AG
%R 10.3390/sym5040313
%X We analyze the point-group symmetries of generic multiband tight-binding models with respect to the transformation properties of the effective interactions. While the vertex functions in the orbital language may transform non-trivially under point-group operations, their point-group behavior in the band language can be simplified by choosing a suitable Bloch basis. We first give two analytically accessible examples. Then, we show that, for a large class of models, a natural Bloch basis exists, in which the vertex functions in the band language transform trivially under all point-group operations. As a consequence, the point-group symmetries can be used to reduce the computational effort in perturbative many-particle approaches, such as the functional renormalization group.
%K correlated electrons
%K point-group symmetries
%K functional renormalization group
%U http://www.mdpi.com/2073-8994/5/4/313