Gamma-surfaces in quasicrystals

The concept of generalized stacking faults and the associated gamma-surfaces provides a useful tool for the analysis of dislocation core structures in crystalline materials. Applied to quasicrystals, suitable Burgers vectors for a given slip plane can be identified by calculating the minima of the gamma-surface. Instead of using a specific interaction model, we motivate a relation between structural properties and a subset of the minima of the gamma-surface. The results agree with calculations based on pair potentials. As a consequence the continuum of possible Burgers vectors in physical space is reduced to a quasiperiodic set, described in terms of a strip-projection method. Further conclusions for the plasticity of quasicrystals are discussed.