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Force-velocity relation and density profiles for biased diffusion in an adsorbed monolayer

O. Benichou·A. M. Cazabat·J. De Coninck·M. Moreau·G. Oshanin
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Abstract

In this paper, which completes our earlier short publication [Phys. Rev. Lett. 84, 511 (2000)], we study dynamics of a hard-core tracer particle (TP) performing a biased random walk in an adsorbed monolayer, composed of mobile hard-core particles undergoing continuous exchanges with a vapor phase. In terms of an approximate approach, based on the decoupling of the third-order correlation functions, we obtain the density profiles of the monolayer particles around the TP and derive the force-velocity relation, determining the TP terminal velocity, V_{tr}, as the function of the magnitude of external bias and other system's parameters. Asymptotic forms of the monolayer particles density profiles at large separations from the TP, and behavior of V_{tr} in the limit of small external bias are found explicitly.

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O. Benichou, A. M. Cazabat, J. De Coninck, M. Moreau, G. Oshanin. 2000-04-26. Force-velocity relation and density profiles for biased diffusion in an adsorbed monolayer. https://doi.org/10.1103/physrevb.63.235413

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