Regensburg 2010 – wissenschaftliches Programm
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CPP: Fachverband Chemische Physik und Polymerphysik
CPP 14: Poster: Interfaces and Thin Films
CPP 14.24: Poster
Montag, 22. März 2010, 16:30–18:00, Poster C
Influence of connectivity on the entropic stiffness of tethered membranes — •Marco Werner1,2 and Jens-Uwe Sommer1,2 — 1Leibniz-Institut für Polymerforschung Dresden, Germany — 2Technische Universität Dresden - Institute for Theoretical Physics
We investigate the static and dynamical properties of tethered structures like membranes and fractal polymer objects using the Bond-Fluctuation-Model in three-dimensional space. Tethered structures can be characterized by the spectral dimension depending on their connectivity. For two-dimensional polymers (perfect membranes) we confirm the picture of an entropic stiffness induced locally by excluded volume interaction, which in turn causes a flat state on larger scales [Y.Kantor and K.Kremer, Phys. Rev. E 48(4), 2490, (1993)]. On the other hand we found fractal structures e.g. Sierpinski gaskets to be crumpled and their fractal dimension to agree with mean-field arguments [M.E.Cates, Phys. Rev. Lett. 53(9), 926, (1984)], whereas Sierpinski carpets are asymptotically flat like perfect membranes. Indeed we found mean field arguments to be self consistent for Sierpinski gaskets but not for Sierpinski carpets. Thus the lower critical dimension for tethered membranes might be below 2 as indicated by an є-expansion [J.A.Aronovitz and T.C.Lubensky, Phys. Rev. Lett. 60(25), 2634, (1988)].