Asymmetric limit cycles within Lorenz chaos induce anomalous mobility for a memory-driven active particle

Area of Science:

• Physics
• Nonlinear Dynamics
• Active Matter Physics

Background:

• Nonequilibrium systems can display unusual responses to external forces, including giant negative mobility (GNM) and giant positive mobility (GPM).
• Previous studies focused on idealized models of passive inertial particles, limiting understanding of active particle dynamics.

Purpose of the Study:

• To investigate anomalous transport behaviors in a memory-driven active particle model.
• To explore the simultaneous emergence of GNM and GPM in a minimal active particle system.

Main Methods:

• Developed a minimal model of a memory-driven active particle, mapping its motion to the Lorenz system.
• Introduced a small bias force to the active particle's Lorenz model to analyze transport properties.

Main Results:

• Uncovered a dynamical mechanism for the simultaneous emergence of GNM and GPM within the parameter space.
• Observed that coexisting asymmetric limit cycles migrate under bias force, leading to anomalous transport.
• Demonstrated that transport behaviors are sensitive to the active particle's memory.

Conclusions:

• The study highlights a general mechanism for anomalous transport in active particles modeled by low-dimensional nonlinear systems.
• This work provides insights into the complex dynamics of active matter, drawing parallels with experimental systems like walking droplets.