2016/10/04 by A. Sarracino, Alessandro Sarracino, Fabio Cecconi +5
Engineering · Physics and Astronomy · #Advanced Thermodynamics and Statistical Mechanics #Classical mechanics #Compressibility #Diffusion #Einstein relation #Fluid Dynamics and Turbulent Flows #Inertia #Laminar flow #Mechanics #Non-equilibrium thermodynamics #Nonlinear system #Particle Dynamics in Fluid Flows #Phase space #Physics #Quantum mechanics #TRACER #Thermodynamics #cond-mat.stat-mech #physics.flu-dyn
paper · pdf · doi:10.1103/physrevlett.117.174501
published as Phys. Rev. Lett. 117, 174501 (2016) · 5 pages, 6 figures, to appear in Physical Review Letters
arxiv created 2016/10/04 · openalex publication_date 2016/10/20 · arxiv updated 2016/10/24 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We study the mobility and the diffusion coefficient of an inertial tracer advected by a two-dimensional incompressible laminar flow, in the presence of thermal noise and under the action of an external force. We show, with extensive numerical simulations, that the force-velocity relation for the tracer, in the nonlinear regime, displays complex and rich behaviors, including negative differential and absolute mobility. These effects rely upon a subtle coupling between inertia and applied force that induces the tracer to persist in particular regions of phase space with a velocity opposite to the force. The relevance of this coupling is revisited in the framework of nonequilibrium response theory, applying a generalized Einstein relation to our system. The possibility of experimental observation of these results is also discussed.