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arXiv · 0809.0197

Dumbbell diffusion in a spatially periodic potential

Jochen Bammert·Steffen Schreiber·Walter Zimmermann
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Abstract

We present a numerical investigation of the Brownian motion and diffusion of a dumbbell in a two-dimensional periodic potential. Its dynamics is described by a Langevin model including the hydrodynamic interaction. With increasing values of the amplitude of the potential we find along the modulated spatial directions a reduction of the diffusion constant and of the impact of the hydrodynamic interaction. For modulation amplitudes of the potential in the range of the thermal energy the dumbbell diffusion exhibits a pronounced local maximum at a wavelength of about 3/2 of the dumbbell extension. This is especially emphasized for stiff springs connecting the two beads.

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Jochen Bammert, Steffen Schreiber, Walter Zimmermann. 2008-09-01. Dumbbell diffusion in a spatially periodic potential. https://doi.org/10.1103/physreve.77.042102

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