arXiv:cond-mat/0609280 · Physical Review B
Luttinger sum rule for finite systems of correlated electrons
J. Kokalj, Peter Prelovšek
Abstract
The validity of the Luttinger sum rule is considered for finite systems of interacting electrons, where the Fermi volume is determined by location of zeros of Green's function. It is shown that the sum rule in the paramagnetic state is evidently violated within the planar $t\text{\ensuremath{-}}J$ model at low doping while for the related Hubbard model, even in the presence of next-nearest-neighbor hopping, no clear-cut exception is found.