Exact moments for trapped active particles: inertial impact on steady-state properties and re-entrance

Manish Patel; Debasish Chaudhuri

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arXiv · 2404.01107

Exact moments for trapped active particles: inertial impact on steady-state properties and re-entrance

Manish Patel·Debasish Chaudhuri

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Abstract

In this study, we investigate the behavior of inertial active Brownian particles in a $d$-dimensional harmonic trap in the presence of translational diffusion. While the solution of the Fokker-Planck equation is generally challenging, it can be utilized to compute the exact time evolution of all time-dependent dynamical moments using a Laplace transform approach. We present the explicit form for several moments of position and velocity in $d$-dimensions. An interplay of time scales assures that the effective diffusivity and steady-state kinetic temperature depend on both inertia and trap strength, unlike passive systems. We present detailed `phase diagrams' using kurtosis of velocity and position showing possibilities of re-entrance.

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Manish Patel, Debasish Chaudhuri. 2024-04-01. Exact moments for trapped active particles: inertial impact on steady-state properties and re-entrance. https://arxiv.org/abs/2404.01107

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