Self-propulsion and self-rotation of an inertial chiral active Ornstein-Uhlenbeck particle

TL;DR

This paper analyzes the transport properties of an inertial chiral active Ornstein-Uhlenbeck particle, revealing unique diffusive behaviors and the influence of chirality and activity on its steady-state dynamics.

Contribution

It provides an exact analytical and numerical study of the transient and steady-state behavior of chiral active particles, highlighting the effects of chirality on diffusion and confinement.

Findings

Chiral active particles show ballistic, sub-diffusive, and diffusive regimes.

Transient confinement due to chirality affects particle dynamics.

Steady-state MSD and MSV depend on chirality and activity duration.

Abstract

We investigate the transport feature of an inertial chiral active Ornstein-Uhlenbeck particle moving on a two-dimensional surface. Using both analytical approach and numerical simulations, we have exactly explored the transient and steady-state behavior of the particle by analyzing the simulated particle trajectories, probability distribution functions for position and velocity, mean square displacement, mean square velocity, and effective kinetic temperature of the medium. From the mean square displacement calculations, we observe that, unlike an inertial active Brownian particle, a chiral active particle manifests an initial ballistic, intermediate sub-diffusive to non-diffusive, and the conventional long-time diffusive behavior. The intermediate sub-diffusive to non-diffusive behavior is prominent for the self-propulsion of an overdamped particle. It can be understood by chirality-induced transient confinement, which persists for short time intervals and diffuses away in the time asymptotic limit or at the steady state. This behavior is further complemented by the exact calculation of mean square velocity or effective kinetic temperature of the medium, which is a decreasing function of the magnitude of chirality. Moreover, the steady-state MSD and MSV are found to have a dependence both on chirality and activity time scale and hence can be controlled by tuning the persistent duration of activity or strength of the chirality of the particle.