A class of Heisenberg models with the orthogonal dimer ground states
arXiv:cond-mat/9904014 · doi:10.1088/0953-8984/11/17/101
Abstract
Extensions of the Shastry-Sutherland model are possible in various ways. In particular, it is possible to construct a natural model in three dimensions which has the exact dimer ground state. Recently found spin gap system SrCu_2(BO_3)_2 has this structure. The exchange constants between the layers is expected to be smaller than the intra-layer couplings. However, the exactness of the dimer state for the three dimensional structure is important to understand why magnetic properties of SrCu_2(BO_3)_2 are described well by the two dimensional model.
3 pages, 5 figures, to appear in Journal of Physics: Condensed Matter