Regensburg 2010 – wissenschaftliches Programm

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MM: Fachverband Metall- und Materialphysik

MM 26: Poster Session

MM 26.47: Poster

Dienstag, 23. März 2010, 14:45–16:30, Poster C

Studies on phason flips by kinetic Monte Carlo simulations — •Hansjörg Lipp and Hans-Rainer Trebin — Institut für Theoretische und Angewandte Physik, Universität Stuttgart, Stuttgart

Neutron scattering experiments [1] indicate that atoms in quasicrystals perform flips between split positions with typical time scales of picoseconds. On the other hand, Edagawa et al. have presented HRTEM images [2], where bright spots are flipping with periods of seconds or even minutes.

To explain this apparent discrepancy, we start from a structure model for d-Al-Cu-Co of Zeger et al. [3], where a ring of ten atoms can perform a jump by four consecutive single atom flips. By applying kinetic Monte Carlo simulations [4], we study how these collective flips, which occur in the different layers of the d-phase can lead to flips detectable by HRTEM on much lower frequency scales.

[1] G. Coddens et al., Phys. Rev. Lett. 78, 4209 (1997)

[2] K. Edagawa et al., Phys. Rev. Lett. 85, 1674 (2000)

[3] G. Zeger and H.-R. Trebin, Phys. Rev. B 54, R720 (1996)

[4] A. B. Bortz et al., J. Comput. Phys. 17, 10 (1975)