It was recalled that dislocation kink solitons in disordered solid solutions provided an example of quasi-particles exhibiting anomalous kinetics: a non-linear dependence of the displacement, x, upon the time, t, x~tδ (δ < 1). In order to describe the dynamic phase transition from the ordinary linear to anomalous regime, the dynamics of a quasiparticle in an energy landscape that performed a correlated random walk on the energy scale was studied. The phase diagram was characterized by the calculated temperature dependence of the threshold driving force, Fth, below which the average velocity of quasiparticles vanished. The

exponent ,δ, of the kinetic equation for the anomalous phase, x~tδ, was determined by simple statistical arguments using the concepts of the so-called optimal fluctuation method. The dependence of the threshold driving force, Fth, upon the concentration of solute atoms and statistical properties of a random energy landscape relevant to disordered solid solutions was calculated. The correlations between steps of the random potential were shown to modify the concentration dependence of Fth, thereby providing a qualitative explanation of experimental data on the dislocation pinning in solid solutions.

Anomalous Mobility of Dislocation Kink Solitons in Disordered Solid Solutions. B.V.Petukhov: Physical Review E, 2008, 77[2], 026601 (9pp)