When does an active bath behave as an equilibrium one?

Abstract

Active baths are characterized by a non-Gaussian velocity distribution and a quadratic dependence with active velocity $v_0$ of the kinetic temperature and diffusion coefficient. While these results hold in over-damped active systems, inertial effects lead to normal velocity distributions, with kinetic temperature and diffusion coefficient increasing as $\sim v_0^{\alpha }$ with $1<\alpha <2$. Remarkably, the late-time diffusivity and mobility decrease with mass. Moreover, we show that the equilibrium Einstein relation is asymptotically recovered with inertia. In summary, the inertial mass restores an equilibrium-like behavior.

8 pages, 9 figures

References in corpus (9)

• Inertial effects of self-propelled particles: from active Brownian to active Langevin motion
• The Einstein relation generalized to non-equilibrium
• Response theory: a trajectory-based approach
• Effective temperatures in inhomogeneous passive and active bidimensional Brownian particle systems
• Active Microrheology in Active Matter Systems: Mobility, Intermittency and Avalanches
• On the Einstein relation between mobility and diffusion coefficient in an active bath
• Active Refrigerators Powered by Inertia
• Microscopic theory for the diffusion of an active particle in a crowded environment
• Exact moments and re-entrant transitions in the inertial dynamics of active Brownian particles

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