Spectral weight contributions of many-particle bound States and continuum.
Cluster expansion methods are developed for calculating the spectral weight contributions of multiparticle excitations--continuum and bound states--to high orders. A complete 13th order calculation is carried out for the alternating Heisenberg chain. For lambda=0.27, relevant to the material Cu(NO3)(2).2.5D(2)O, we present detailed spectral weights for the two-triplet continuum and all bound states. We also examine the variation of the relative weights of one- and two-particle states with bond alternation from the dimerized to the uniform chain limit.
Zheng
Weihong
W
School of Physics, University of New South Wales, Sydney NSW 2052, Australia.
Hamer
Chris J
CJ
Singh
Rajiv R P
RR