Critical dynamics of ballistic and Brownian particles in a heterogeneous environment

@article{citeulike:2782588, abstract = {The dynamic properties of a classical tracer particle in a random, disordered medium are investigated close to the localization transition. For Lorentz models obeying Newtonian and diffusive motion at the microscale, we have performed large-scale computer simulations, demonstrating that universality holds at long times in the immediate vicinity of the transition. The scaling function describing the crossover from anomalous transport to diffusive motion is found to vary extremely slowly and spans at least five decades in time. To extract the scaling function, one has to allow for the leading universal corrections to scaling. Our findings suggest that apparent power laws with varying exponents generically occur and dominate experimentally accessible time windows as soon as the heterogeneities cover a decade in length scale. We extract the divergent length scales, quantify the spatial heterogeneities in terms of the non-Gaussian parameter, and corroborate our results by a thorough finite-size analysis.}, author = {H\"{o}fling, Felix and Munk, Tobias and Frey, Erwin and Franosch, Thomas }, citeulike-article-id = {2782588}, doi = {10.1063/1.2901170}, journal = {Journal of Chemical Physics}, keywords = {randommatrix, simulation}, pages = {164517+}, posted-at = {2008-05-10 09:44:51}, priority = {0}, title = {Critical dynamics of ballistic and Brownian particles in a heterogeneous environment}, url = {http://dx.doi.org/10.1063/1.2901170}, volume = {128}, year = {2008} }

TY - JOUR ID - citeulike:2782588 L3 - citeulike-article-id:2782588 TI - Critical dynamics of ballistic and Brownian particles in a heterogeneous environment JF - Journal of Chemical Physics VL - 128 SP - 164517 N2 - The dynamic properties of a classical tracer particle in a random, disordered medium are investigated close to the localization transition. For Lorentz models obeying Newtonian and diffusive motion at the microscale, we have performed large-scale computer simulations, demonstrating that universality holds at long times in the immediate vicinity of the transition. The scaling function describing the crossover from anomalous transport to diffusive motion is found to vary extremely slowly and spans at least five decades in time. To extract the scaling function, one has to allow for the leading universal corrections to scaling. Our findings suggest that apparent power laws with varying exponents generically occur and dominate experimentally accessible time windows as soon as the heterogeneities cover a decade in length scale. We extract the divergent length scales, quantify the spatial heterogeneities in terms of the non-Gaussian parameter, and corroborate our results by a thorough finite-size analysis. KW - randommatrix KW - simulation AU - H\"{o}fling, Felix AU - Munk, Tobias AU - Frey, Erwin AU - Franosch, Thomas PY - 2008/// UR - http://dx.doi.org/10.1063/1.2901170 ER -