Multi-particle excitations and spectral densities in quantum spin-systems
Strongly Correlated Electrons
2009-11-07 v1
Abstract
The excitation spectrum of the 2-leg S=1/2 Heisenberg ladder is examined perturbatively. Using an optimally chosen continuous unitary transformation we expand the Hamiltonian and the Raman operator about the limit of isolated rungs leading to high order series expansions allowing to calculate spectral densities quantitatively. The 2-particle sector is examined for total momentum k=0. We show that triplet-triplet interaction gives rise to a band splitting.
Keywords
Cite
@article{arxiv.cond-mat/0107526,
title = {Multi-particle excitations and spectral densities in quantum spin-systems},
author = {Christian Knetter and Kai P. Schmidt and Götz S. Uhrig},
journal= {arXiv preprint arXiv:cond-mat/0107526},
year = {2009}
}
Comments
2 pages, 1 figure; submitted to the proceedings of the SCES2001 conference (Physica B)