Speaker
Description
We report results on the unconventional finite-temperature properties of the localized singlet-triplet excitations in the 2D frustrated magnet $SrCu_2(BO_3)_2$. Performing inelastic neutron scattering, singlet-triplet modes were separated in energy with an applied magnetic field, so that their damping could be studied independently. The $Q$-dependence of the damping mechanism was determined by analysis of the anomalous lineshapes measured at 6.3K, using the two-components damping mechanism proposed in a correlated decay model. Each excited triplet appears equivalently distributed in space, while the applied field creates different thermal populations for $S^z=0,±1$ modes. While the Q-dependence of the damping is equivalent for each mode, we show that triplets undergo faster damping close to $(\pi,\pi)$.
