A two-dimensional dislocation system on a triangular lattice was studied by means of Monte Carlo simulation. Particular emphasis was put on the effect of external stresses. For a given value of the stress, only pairs of dislocations with opposite Burgers vectors were present to a considerable extent in the system at low temperatures. With increasing temperature, unbinding of the dislocation pairs occurred and led to a phase transition. The present results were in agreement with the Kosterlitz-Thouless-Berezinskii theory for zero stress and the Khantha model for non-zero stress. The stress dependence of the critical temperature, as obtained using the present simulations, was in very good agreement with the analytical expression derived by Khantha et al. It was found that stress-dependent dislocation currents appeared in the system and exhibited a behaviour which was similar to that of the electric current during the insulator-metal transition in layered superconductors.

Monte Carlo Studies of Two-Dimensional Dislocation Systems in Applied External Stress. S.Pafka, J.Cserti, G.Tichy: Modelling and Simulation in Materials Science and Engineering, 1998, 6[5], 507-19