Differential and absolute negative mobility in steady laminar flows

  Nonlinear response in out-of-equilibrium systems can show counter-intuitive behaviors, for instance cases where the force increases but the response decreases (negative differential mobility). Sometimes the response crosses zero and changes sign with respect to the force (absolute negative mobility). In classical physics this is usually observed within complicate models with obstacles and traps. We have demonstrated such complex non-linear phenomena in a much simpler and realistic system, ie. an inertial particles drag through a fluid with vortices.

 

 

 

A. Sarracino, F. Cecconi, A. Puglisi and A. Vulpiani
Nonlinear response of inertial tracers in steady laminar flows: differential and absolute negative mobility
Phys. Rev. Lett. 117, 174501 (2016)