Kinetics of Discrete Kinks and Domain Walls

The kinetics of kinks and domain walls in quasi-one-dimensional systems is described within the framework of a model intermediate between the sharp kink model and the continuum model of an elastic string. The effects resulting from the discrete structure of crystalline materials are considered, including the periodic inhomogeneity of the energy relief for kink migration. Within a transparent approximation using a minimum number of internal variables, the dependence of the Peierls barriers on the driving force is calculated, and the transition between static and dynamic regimes is described. The theory is based on the universal Frenkel–Kontorova model and can be applied to extended systems of various nature.