Zero-Temperature Spin Dynamics of Model Spin-Glass Hamiltonians

Computer modeling techniques are used to obtain information about the spin dynamics of model spin-glass Hamiltonians in the zero-temperature limit. The density of states and dynamic structure factor are computed numerically for the Edwards-Anderson and Mattis models with Heisenberg interactions. We find no evidence for spin-wave modes in the former; the latter shows spin-wave behavior characteristic of a disordered XY model.