Spin dynamics of Shastry-Sutherland model

We employ finite-temperature Lanczos technique on finite clusters to compute dynamical spin structure factor of Shastry-Sutherland model, which describes quasi-two-dimensional dimer spin-liquid SrCu2(BO3)2 compound. Unusual temperature dependence of calculated spectra is in agreement with inelastic neutron scattering measurements. Introduction of nonmagnetic impurities leads to the formation of small anisotropic magnetic polarons surrounding impurity sites. Additional peaks due to finite doping appear in the spin structure factor.