Finite-size calculations of spin-lattice relaxation rates in Heisenberg spin-ladders
arXiv:cond-mat/0002142
Abstract
Calculations of nuclear spin-lattice relaxation rates are carried out by means of exact diagonalization on small (2 x 6) antiferromagnetic Heisenberg ladders, using the simplest forms permitted by symmetry for the hyperfine couplings for the three nuclear sites in Cu2O3 ladders. Several values of the rung/chain exchange ratio have been considered. Comparisons with experimental results, field theoretic calculations, and the Gaussian approximation highlight some open problems.
13 pages (including 4 figures) preprint format, uses Revtex4 (beta 3)