Model for a multicomponent quantum system
Abstract
In a recent paper, Lai introduced a latticegas model. In this paper we generalize Lai's model, making application to various systems such as dilute Heisenberg magnets, higherspin systems, and a lattice of SU(3) triplets. By a careful consideration of general thermodynamic stability, and by variational arguments, we demonstrate Lai's solution to be incorrect, and in turn produce the correct solution in this case and in other cases including higherdimensional models. The remaining cases we treat in one dimension by Bethe's ansatz, reducing the problem to coupled integral equations. We locate the singularities of the groundstate energy in the phase plane; and we explicitly calculate the absolutegroundstate energy, excitations above the absolute ground state, and the first correction to the absolute ground state for small concentrations of impurities.
 Publication:

Physical Review B
 Pub Date:
 November 1975
 DOI:
 10.1103/PhysRevB.12.3795
 Bibcode:
 1975PhRvB..12.3795S