Regensburg 2000 – wissenschaftliches Programm

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DY: Dynamik und Statistische Physik

DY 42: Wachstum und Grenzfl
ächen

DY 42.2: Vortrag

Donnerstag, 30. März 2000, 11:15–11:30, H2

Fragmentation, 2D-Bubbles and Coarsening: Decay of Ag-Networks on a Liquid Surface — •Bo Yang^1,2, Jens Ritter¹, Matthias Wuttig¹, Zheng-Kuan Jiao², and Thomas Michely¹ — ¹I. Physikalisches Institut, RWTH-Aachen, 52056 Aachen — ²Department of Physics, Zhejiang University, 310027 Hangzhou, China

Ag-networks are formed on a liquid surface by vapor phase deposition of Ag under high vacuum conditions. These networks result from aggregation of mobile Ag-clusters on the liquid surface and are only a few atomic layers thick. The decay of the networks is investigated in situ by video microscopy. Fluctations in the width of the network branches may lead to branch rupture. Depending on the frequency of branch rupture, different decay scenarios evolve. Large compact, but flat clusters are formed as a consequence of frequent branch rupture. The number density of these clusters decreases with time by cluster diffusion and coalescence. Probably the most interesting situation results, when branch rupture leads to detachment of intact network meshes. These network meshes rearrange rapidly by surface diffusion into metastable 2D-bubbles or Ag-rings. For rare breaking of network branches, network coarsening could be observed for several days. During the observation time, the width of the network meshes increases by two orders of magnitude up to several hundred µm. The scaling behavior of the coarsening is discussed.