Sat, 19 Jul 2008 03:00:52 BST CiteULike: dchen's Gutt http://www.citeulike.org/user/dchen/author/Gutt CiteULike.org en-gb Copyright © 2004-2008 citeulike.org http://www.citeulike.org/user/dchen/article/2563095 <i>Physical Review Letters, Vol. 98, No. 4. (2007)</i><br /><br />X-ray photon-correlation spectroscopy is used to measure the dynamic structure factor f(q,) of gold particles moving on the surface of thin polymer films. Above the glass transition of the polymer the peculiar form f(q,)~exp[-()] is found with 0.7<<1.5, depending on sample age and temperature. The relaxation rates scale linearly with q, excluding a simple Brownian diffusive motion. This type of behavior, already observed in aging bulk soft matter systems, is explained by a power law distribution of particle velocities due to ballistic motion. Two-Dimensional Dynamics of Metal Nanoparticles on the Surface of Thin Polymer Films Studied with Coherent X Rays S Streit C Gutt V Chamard A Robert M Sprung H Sternemann M Tolan doi:10.1103/PhysRevLett.98.047801 Physical Review Letters, Vol. 98, No. 4. (2007) 2008-03-19T17:03:19-00:00 2007 Physical Review Letters 98 4 APS 2007 diffusion experiment film nano polymer