The pair interaction between crystal dislocations was systematically explored by analyzing particle trajectories of two-dimensional colloidal crystals measured by video microscopy. The resulting pair energies were compared to Monte Carlo data and to predictions derived from the standard Hamiltonian of the elastic theory of dislocations. Good agreement was found with respect to the distance and temperature dependence of the interaction potential, but not regarding the angle dependence where discrete lattice effects became important. The results generally confirmed that the dislocation Hamiltonian permitted a quantitative understanding of the formation and interaction energies of dislocations in 2-dimensional crystals.

Pair Interaction of Dislocations in Two-Dimensional Crystals. C.Eisenmann, U.Gasser, P.Keim, G.Maret, H.H.von Grünberg: Physical Review Letters, 2005, 95[18], 185502 (3pp)