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Two-Dimensional Diffusion in the Presence of Topological Disorder

Ligang Chen·Michael W. Deem
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Abstract

How topological defects affect the dynamics of particles hopping between lattice sites of a distorted, two-dimensional crystal is addressed. Perturbation theory and numerical simulations show that weak, short-ranged topological disorder leads to a finite reduction of the diffusion coefficient. Renormalization group theory and numerical simulations suggest that longer-ranged disorder, such as that from randomly placed dislocations or random disclinations with no net disclinicity, leads to subdiffusion at long times.

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Ligang Chen, Michael W. Deem. 2003-08-29. Two-Dimensional Diffusion in the Presence of Topological Disorder. https://doi.org/10.1103/physreve.68.021107

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