Abstract
Phys. Rev. E 100, 042610 (2019) We computationally study the behavior of underdamped active Brownian
particles in a sheared channel geometry. Due to their underdamped dynamics, the
particles carry momentum a characteristic distance away from the boundary
before it is dissipated into the substrate. We correlate this distance with the
persistence of particle trajectories, determined jointly by their friction and
self-propulsion. Within this characteristic length, we observe new and
counterintuitive phenomena stemming from the interplay of activity,
interparticle interactions, and the boundary driving. Depending on values of
friction and self-propulsion, interparticle interactions can either aid or
hinder momentum transport. More dramatically, in certain cases we observe a
flow reversal near the wall, which we correlate with an induced polarization of
the particle self-propulsion directions. We rationalize these results in terms
of a simple kinetic picture of particle trajectories.