%0 Journal Article
%T Direct Evidence for the Localized Single-Triplet Excitations and the Dispersive Multi-Triplets Excitations in SrCu2(BO3)2
%A H. Kageyama
%A M. Nishi
%A N. Aso
%A K. Onizuka
%A T. Yosihama
%A K. Nukui
%A K. Kodama
%A K. Kakurai
%A Y. Ueda
%J Physics
%D 2000
%I arXiv
%R 10.1103/PhysRevLett.84.5876
%X We performed inelastic neutron scattering on the 2D Shastry-Sutherland system SrCu2(11BO3)2 with an exact dimer ground state. Three energy levels at around 3, 5 and 9 meV were observed at 1.7 K. The lowest excitation at 3.0 meV is almost dispersionless with a bandwidth of 0.2 meV at most, showing a significant constraint on a single-triplet hopping owing to the orthogonality of the neighboring dimers. In contrast, the correlated two-triplets excitations at 5 meV exhibit a more dispersive behavior.
%U http://arxiv.org/abs/cond-mat/0005342v1