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arXiv · 2103.06659

Long-time diffusion and energy transfer in polydisperse mixtures of particles with different temperatures

Efe Ilker·Michele Castellana·Jean-François Joanny
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Abstract

Evidence suggests that the transport rate of a passive particle at long timescales is enhanced due to interactions with the surrounding active ones in a size- and composition-dependent manner. Using a system of particles with different temperatures, we probe these effects in dilute solutions and derive long-time friction and self-diffusion coefficients as functions of volume fractions, sizes and temperatures of particles in $d=2$ and 3 dimensions. Thus, we model excluded-volume interactions for nonequilibrium systems but also extend the scope to short-range soft potentials and compare our results to Brownian-dynamics simulations. Remarkably, we show that both viscosity and energy flux display a nonlinear dependence on size. The simplicity of our formalism allows to discover various interesting scenarios that can be relevant for biological systems and active colloids.

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Efe Ilker, Michele Castellana, Jean-François Joanny. 2021-03-11. Long-time diffusion and energy transfer in polydisperse mixtures of particles with different temperatures. https://doi.org/10.1103/physrevresearch.3.023207

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