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Absolute negative mobility induced by nonlinear interparticle coupling.
Wenjun Liu1, Haojie Luo1, Lei Wang1
1Renmin University of China, School of Physics, Beijing Key Laboratory of Opto-electronic Functional Materials and Micro-nano Devices, and Key Laboratory of Quantum State Construction and Manipulation (Ministry of Education), Beijing 100872, People's Republic of China.
Physical Review. E
|March 20, 2026
Summary
Nonlinear coupling in Brownian particles can induce absolute negative mobility. This occurs due to phase locking, allowing controlled movement against the applied force in microscopic systems.
Area of Science:
- Statistical physics
- Nonlinear dynamics
- Microscopic systems
Background:
- Brownian particles in periodic potentials are fundamental in statistical physics.
- Understanding particle transport under external forces is crucial for micro-machine design.
- Nonlinear interactions can lead to complex emergent behaviors.
Purpose of the Study:
- To investigate the role of nonlinear coupling in inducing absolute negative mobility.
- To explore the mechanism of phase locking in achieving directed motion.
- To analyze the system's robustness against external noise.
Main Methods:
- Theoretical study of two inertial Brownian particles.
- Analysis of systems with nonlinear coupling in a symmetric periodic potential.
- Application of unbiased harmonic driving and a constant external force.
Main Results:
- Absolute negative mobility was induced by nonlinear coupling.
- Phase locking was identified as the key mechanism for negative mobility.
- Controlled trajectories with a stable phase difference were achieved.
- Robustness against external noise was improved in certain scenarios.
Conclusions:
- Nonlinear interactions are a powerful tool for controlling microscopic system dynamics.
- Phase locking provides a pathway to achieve negative mobility in Brownian systems.
- This work broadens methods for tuning collective mobility via internal interactions.
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