Dislocation dynamics in a dodecagonal quasiperiodic structure

Abstract

We have developed a set of numerical tools for the quantitative analysis of defect dynamics in quasiperiodic structures. We have applied these tools to study dislocation motion in the dynamical equation given by Lifshitz and Petrich in 1997, the steady-state solutions of which include a quasiperiodic structure with dodecagonal symmetry. Arbitrary dislocations, parameterized by the homotopy group of the D-torus, are injected as initial conditions and quantitatively followed as the equation evolves in real time. We show that for strong diffusion the results for dislocation climb velocity are similar for the dodecagonal and the hexagonal patterns, but that for weak diffusion the dodecagonal pattern exhibits a unique pinning of the dislocation reflecting its quasiperiodic structure.

Acknowledgement

This research was supported by the Israel Science Foundation under grant 278/00.