Active diffusion in disordered complex polymer networks
Abstract
Living cells are active entities that exhibit rich dynamical behaviors that often deviate from classical Brownian motion. In particular, the motion of particles in such environments often displays out-of-equilibrium or active diffusion. Motivated by this, we simulate the diffusion of active Brownian particles (ABPs) in three-dimensional disordered polymer networks constructed by random cross-linking of semiflexible filaments. Activity in the presence of disorder gives rise to remarkable dynamic properties of particles therein: a disorder-induced active ratchet effect and Fickian yet non-Gaussian diffusion, captured by an extended diffusing-diffusivity model with fluctuating propulsion and local diffusivity. These results reveal generic mechanisms by which structural disorder and non-equilibrium activity cooperate to shape transport in crowded biological and synthetic media. If time is allowed, recent ongoing work about power spectrum and ratchet currents of active particles will be shortly introduced.
