Tunneling Nucleation of Kink Pairs on Dislocations in the Peierls Potential Relief with Random Distortions

摘要

In view of the recent increased interest in the mechanical properties of quantum crystals, the study of the low-temperature dynamics of dislocations is necessary. Tunneling through the barriers created by periodic relief of the crystal lattice, which leads to the formation of pairs of kinks, makes an important contribution to this dynamics. Incomplete perfection of crystals often imposes uncontrollable perturbations that modify the features of the process of the tunneling nucleation of kinks. This article presents the modelling of perturbation effect by the random fields of internal stresses such as spatial "Gaussian noise." The average value of the realizations of the rate of quantum-mechanical tunnel formation of kink pairs in the random fields is calculated. It is shown that even perturbations that are relatively weak in comparison with the crystalline relief lead to a significant modification of the kink formation rate dependence on a driving force. Published by AIP Publishing.