|
|
Sfb 288 Differential Geometry and Quantum Physics |
Abstract for Sfb Preprint No. 179
Ground state and low excitations of an integrable chain with alternating spins St. Meissner, B.-D. Doerfel
An anisotropic integrable spin chain, consisting of spins s=1 and s=2, is investigated [1]. It is characterized by two real parameters c1 and c2, the coupling constants of the spin interactions. For the case c1<0 and c2<0 the ground state configuration is obtained by means of thermodynamic Bethe ansatz. Furthermore the low excitations are calculated. It turns out, that apart from free magnon states being the holes in the ground state rapidity distribution, there exist bound states given by special string solutions of Bethe ansatz equations (BAE) in analogy to [13]. The dispersion law of these excitations is calcula- ted numerically.
Get a gzip-compressed PostScript copy of this preprint
preprint179.ps.gz (65 kB)