The dynamical structure factor S(q, w) of the K-component (K = 2, 3, 4) spin chain with a 1/r2 interaction is derived exactly at zero temperature for the arbitrary size of the system. The result is interpreted in terms of a free quasiparticle picture which is a generalization of the spinon picture in the SU(2) case. The excited states consist of K quasiparticles each of which is characterized by a set of K − 1 quantum numbers. Divergent singularities of s(q, w) at the spectral edges are derived analytically. The analytic result is checked numerically for finite systems.
ASJC Scopus subject areas
- Physics and Astronomy(all)