Enhancing Diffusion with Active Particles in a Fluctuating Environment

Mass transport and diffusion in porous environments has been widely studied and characterized. In many studies, the porous environment is assumed to be a static structure, however, in nature, these environments are dynamic, having pores of constantly fluctuating size. Together with experimentalists who are able to isolate the effect of environmental fluctuations on passive particles, we aim to model active particles to further study the effect of a dynamic environment on diffusion. We employ Brownian Dynamics in the HOOMD-blue particle simulation toolkit to model active particles diffusing through a dynamic porous environment. By tuning the forces at work in the model, we are able to recover many of the remarkable dynamics observed in experiments. Further, we can explore questions about the system, such as the effects of pore geometry and active force magnitude, which are difficult to assess in experiment alone. Knowledge of such effects lay the groundwork for engineering the diffusion of a particle by controlling its environment.