Collective behaviors of self-propelled particles with tunable alignment angles.

Abstract

We present an aligning active matter model by extending the nematic alignment rule in self-propelled rods to tunable alignment angles, as represented by the collision of cone-shaped particles. Nonvanishing alignment angles introduce frustration in the many-body interactions, and we investigate its effect on the collective behavior of the system. Through numerical simulations of an agent-based microscopic model, we find that the system exhibits distinct phenomenology compared to the original self-propelled rods. In particular, antiparallel bands are observed in an intermediate parameter range. The linear stability analysis of the continuum description derived from the Boltzmann approach demonstrates qualitative consistency with the microscopic model, while frustration due to many-body interactions in the latter destabilizes homogeneous nematic order over a wide range of the alignment angle.