Fast and slow relaxations in the free energy landscape

We present a phenomenological understanding of the fast and slow relaxations in super cooled liquids on the basis of the free energy landscape (FEL). The dynamics of a representative point in the FEL is assumed to obey the time-dependent Ginzburg–Landau type (TDGL) equation with the FEL as the driving potential. We analyze the dynamical structure factor for a toy model and demonstrate that the fast and slow relaxations are determined by jump motion among basins and stochastic motion within a basin, respectively and that the relaxation time of the fast process is determined by the curvature of the FEL around a local minimum.