Tunneling nucleation of kink pairs on dislocations in the Peierls potential relief with random distortions
Institute of Cristallography Russian Academy of Sciences, Leninskii prosp., 59, Moscow, 119333, Russia
Received March 13, 2018, published online July 26, 2018
Due to the recent increased interest in the mechanical properties of quantum crystals, there is a need to study the low-temperature dynamics of dislocations. Tunneling through the barriers created by the periodic relief of the crystal lattice, which leads to the formation of pairs of kinks, makes an important contribution to this dynamics. The lack of perfection of the crystals imposes often uncontrolled perturbations, modifying the features of the process of the tunneling formation of kinks. The perturbations are modeled by the random fields of internal stresses such as spatial "Gaussian noise". The average over realizations of random fields rate of quantum-mechanical tunnel formation of the kink pairs 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 the driving force.
Key words: quantum crystals, kinks, tunneling, random internal stresses.