Speaker
Description
Spinning objects moving through air or liquids experience a Magnus force, a phenomenon widely exploited in ball sports and significant in various scientific and engineering applications. Opposed to large objects where Magnus forces are strong, they are only weak at small scales and eventually vanish for overdamped micron-sized particles in simple liquids. Here we demonstrate an about one-million-fold enhanced Magnus force of spinning colloids in viscoelastic fluids. Such fluids are characterized by a time-delayed response to external perturbations which causes a deformation of the fluidic network around the moving particle.
We further develop a general theory for spinning particles in a non-Markovian bath. Without any applied force, the interplay between rotation and stochastic noise-induced local deformations leads to enhanced diffusion. Our theory also uncovers that for a spinning particle, orthogonal displacement components are correlated. These correlations are non-local in time and exhibit properties akin to the Magnus deflection. We present experimental evidence supporting these phenomena in viscoelastic fluids
References
1) Memory-induced Magnus effect (Nature Physics 19,(2023))
Xin Cao, Debankur Das, Niklas Windbacher, Felix Ginot, Matthias Kruger, Clemens Bechinger.
2) Spinning Non-Markovian Brownian particle (to be submitted)
Debankur Das, Niklas Windbacher, Matthias Kruger, Clemens Bechinger.
