Spatio-temporal dynamics of a single active particle
Thomas Franosch, Institut für Theoretische Physik, Universität Innsbruck
Mo, 30.05.2022, 13:30 Uhr, P603
The active Brownian particle (ABP) model has become a paradigm for dynamics far from equilibrium and has attracted considerable attention in the statistical-physics/soft-matter community . In this model particles undergo directed motion along their axis of orientation which is subject to orientational diffusion. While it is rather easy to simulate the dynamics of such agents in a prescribed potential landscape, analytical progress even for the simplest set-ups has been difficult. In the presentation I will present exact solutions for the spatio-temperaol dynamics for three paradigmatic problems: the free particle [2,3], the motion in a uniform gravitational field as described by the equations of motion of Ref. , as well as the dynamics in a harmonic well. For each case we derive the corresponding Fokker-Planck equation and use techniques familiar from quantum mechanics to provide a complete solution. Each of the three examples displays striking differences from the their passive counterparts, such as oscillatory behavior in the intermediate scattering functions, the emergence of a resonance in the effective diffusion coefficient or non-monotonic behavior in the velocity-autocorrelation function.
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