Domino Effects in Photoinduced Structural Change in One-Dimensional Systems

The possibility of occurrence of cooperative structural changes is investigated using a minimal model composed of localized electrons and classical lattices under the adiabatic approximation. In particular, the relaxation after one-photon absorption at a site is examined in detail. This relaxation proceeds in two steps. First, a local structural change is created due to the lattice relaxation associated with the local electronic excitation. After the spontaneous emission of a photon, this local structural change (a) remains locally, (b) induces a global structural change cooperatively, or (c) disappears and returns to the initial phase. Dynamical features of the case (b) are shown to be characterized by the domino effect. This global structural change occurs only when the intersite interaction is short-ranged and moderately strong.