Time-dependent evolution of double-well potentials to model structural anomalies

Abstract

The time dependence of a nonlinear model Hamiltonian is investigated in order to evaluate the time scale where structural anomalies in perovskite-based materials can be observed by specific experimental methods. It is shown that the appearance of double-well-related features is extremely sensitive to the time scale and that fluctuating polarization domains separated by domain walls have different freezing temperatures than their walls. The domain walls have kink or pulse exiton-type character and may decay into a dynamic or static charge transfer process for decreasing velocities. Possible relations to structural anomalies found in high-T _c superconductors are discussed.