The Structure of Operators in Effective Particle-Conserving Models
Strongly Correlated Electrons
2009-11-10 v1
Abstract
For many-particle systems defined on lattices we investigate the global structure of effective Hamiltonians and observables obtained by means of a suitable basis transformation. We study transformations which lead to effective Hamiltonians conserving the number of excitations. The same transformation must be used to obtain effective observables. The analysis of the structure shows that effective operators give rise to a simple and intuitive perspective on the initial problem. The systematic calculation of n-particle irreducible quantities becomes possible constituting a significant progress. Details how to implement the approach perturbatively for a large class of systems are presented.
Keywords
Cite
@article{arxiv.cond-mat/0306333,
title = {The Structure of Operators in Effective Particle-Conserving Models},
author = {Christian Knetter and Kai P. Schmidt and Goetz S. Uhrig},
journal= {arXiv preprint arXiv:cond-mat/0306333},
year = {2009}
}
Comments
12 pages, 1 figure, accepted by J. Phys. A: Math. Gen