Dynamical phase diagram of the van Hemmen model of spin glass

The dynamical behaviour of the van Hemmen model of spin glass is studied by comparing the time evolution of two configurations subjected to the same thermal noise. It was found that the system undergoes several dynamical phase transitions among the paramagnetic, ferromagnetic, spin-glass and mixed phases, The dynamical phase diagram seems to be in good agreement with the static one. In the spin glass phase, the system presents a quite different dynamical behaviour from that found in short-range spin glass models as well as in the Sherrington-Kirkpatrick model.