Dresden 2009 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
MM: Fachverband Metall- und Materialphysik
MM 40: Quasicrystals I
MM 40.3: Vortrag
Donnerstag, 26. März 2009, 10:45–11:00, IFW D
In search of multipolar order on the Penrose tiling — •Elena Y. Vedmedenko1, Ron Lifshitz2, and S. Even-Dar Mandel2 — 1University of Hamburg, Jungiusstr. 11, 20355 Hamburg — 2Tel Aviv University, 69978 Tel Aviv, Israel
We use Monte Carlo calculations to analyse multipolar ordering on the Penrose tiling, relevant for two-dimensional molecular adsorbates on quasicrystalline surfaces and for nanomagnetic arrays. Our initial investigations are restricted to multipolar rotors of rank one through four positioned on the vertices of the rhombic Penrose tiling. At first sight, the ground states of odd-parity multipoles seem to exhibit long-range order, in agreement with previous investigations of dipolar systems. Yet, careful analysis performed here establishes that long-range order is absent for all types of rotors, and only short-range order exists. Nevertheless, we show here that short-range order suffices to yield a superstructure in the form of the decagonal Hexagon-Boat-Star tiling. [1] E. Y. Vedmedenko, S. Even-Dar Mandelb and R. Lifshitz, Phil. Mag. 88, 2197 (2008).