  We employ computer simulations to study the dynamics of a self-propelled
spherical tracer particle in a viscoelastic medium, made of a long polymer
chain. Here, the interplay between viscoelasticity, stickiness, and activity
(self-propulsion) brings additional complexity to the tracer dynamics. Our
simulation shows that on increasing the stickiness of the tracer particle to
the polymer beads, the dynamics of the tracer particle slows down as it gets
stuck to the polymer chain, and moves along with it. But with increasing the
self-propulsion velocity, the dynamics gets enhanced. In case of increasing
stickiness as well as activity, the non-Gaussian parameter (NGP) exhibits
non-monotonic behavior, which also shows up in the re-scaled self part of the
van-Hove function. Non-Gaussianity results owing to the enhanced binding
events, and the sticky motion of the tracer along with the chain with
increasing stickiness. On the other hand, with increasing activity, initially
non-Gaussianity increases as the tracer moves through the heterogenous
polymeric environment but for higher activity, escapes resulting negative NGP.
For higher values of stickiness, the trapping time distributions of the passive
tracer particle broadens and have long tails. On the other hand, for a given
stickiness with increasing self-propulsion force, the same becomes narrower and
have short tails. We believe that our current simulation study will be helpful
in elucidating the complex motion of activity-driven probes in viscoelastic
media.
