Crowding competes with trapping to enhance interfacial diffusion

Mislav Cvitković; Dipanwita Ghanti; Niklas Raake; Ana-Sunčana Smith

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arXiv · 2106.12965

Crowding competes with trapping to enhance interfacial diffusion

Mislav Cvitković·Dipanwita Ghanti·Niklas Raake·Ana-Sunčana Smith

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Abstract

Diffusion in the crowded environments of the biological membranes or materials interfaces often involves intermittent binding to surface proteins or defects. To account for this situation we study a 2-dimensional lattice gas in a field of immobilized traps. Using kinetic Monte Carlo simulations, we calculate the effective diffusion coefficient in the long-time limit as a function of the traps and particle densities. We find a remarkable result - an increase of the diffusion coefficient with particle density, an effect that we coin as crowding-enhanced diffusion. We rationalize this result using scaling arguments and the master equation approach.

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Mislav Cvitković, Dipanwita Ghanti, Niklas Raake, Ana-Sunčana Smith. 2021-06-24. Crowding competes with trapping to enhance interfacial diffusion. https://arxiv.org/abs/2106.12965

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