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arXiv · 2011.02444

Scaling study of diffusion in dynamic crowded spaces

H. Bendekgey·G. Huber·D. Yllanes
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Abstract

We formulate a scaling theory for the long-time diffusive motion in a space occluded by a high density of moving obstacles in dimensions 1, 2 and 3. Our tracers diffuse anomalously over many decades in time, before reaching a diffusive steady state with an effective diffusion constant $D_\mathrm{eff}$, which depends on the obstacle diffusivity and density. The scaling of $D_\mathrm{eff}$, above and below a critical regime, is characterized by two independent critical parameters: the conductivity exponent $\mu$, also found in models with frozen obstacles, and an exponent $\psi$, which quantifies the effect of obstacle diffusivity.

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BibTeXRIS

H. Bendekgey, G. Huber, D. Yllanes. 2020-11-04. Scaling study of diffusion in dynamic crowded spaces. https://doi.org/10.1088/1751-8121%2Fad8496

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