Self-diffusion in sheared colloidal suspensions: violation of fluctuation-dissipation relation
1Department of Chemistry, Colorado State University, Fort Collins, Colorado 80525, USA.
Physical Review Letters
|November 5, 2004
Abstract:
Using memory-function formalism we show that in sheared colloidal suspensions the fluctuation-dissipation theorem for self-diffusion, i.e., Einstein's relation between self-diffusion and mobility tensors, is violated and propose a new way to measure this violation in Brownian dynamics simulations. We derive mode-coupling expressions for the tagged particle friction tensor and for an effective, shear-rate dependent temperature.
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