Nonlinear nonequilibrium quantum dynamics of photoinduced structural phasetransitions

For the photoinduced ionic --> neutral phase transition in the organic char ge transfer crystal TTF-CA, we, at first, theoretically propose an adiabati c path of this transition, which starts from a single charge transfer excit on in ionic phase, but finally reaches a neutral domain with a macroscopic size. In the next, using a more simplified model, we theoretically study th e nonequilibrium quantum time-evolution dynamics of the photoinduced-phase transition, with a special emphasis on the multistability of the ground sta te and the exciton proliferation, both of which characterize the nonlineari ty of this system. (C) 2000 Elsevier Science B.V. All rights reserved.