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arXiv · 1205.2243

Bulk-mediated diffusion on a planar surface: full solution

Aleksei V. Chechkin·Irwin M. Zaid·Michael A. Lomholt·Igor M. Sokolov·Ralf Metzler
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Abstract

We consider the effective surface motion of a particle that intermittently unbinds from a planar surface and performs bulk excursions. Based on a random walk approach we derive the diffusion equations for surface and bulk diffusion including the surface-bulk coupling. From these exact dynamic equations we analytically obtain the propagator of the effective surface motion. This approach allows us to deduce a superdiffusive, Cauchy-type behavior on the surface, together with exact cutoffs limiting the Cauchy form. Moreover we study the long-time dynamics for the surface motion.

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Aleksei V. Chechkin, Irwin M. Zaid, Michael A. Lomholt, Igor M. Sokolov, Ralf Metzler. 2012-05-10. Bulk-mediated diffusion on a planar surface: full solution. https://doi.org/10.1103/physreve.86.041101

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