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Fluctuating magnetic field induced resonant activation.
Shrabani Mondal1, Sudip Das1, Alendu Baura1
1Department of Chemistry, Visva-Bharati, Santiniketan 731235, India.
The Journal of Chemical Physics
|December 16, 2014
Summary
A fluctuating magnetic field affects Brownian particle behavior in open systems. This random field can induce resonant activation and alter barrier crossing rates, challenging traditional physics principles.
Area of Science:
- Statistical physics
- Non-equilibrium thermodynamics
- Complex systems
Background:
- Brownian motion describes particle movement due to random collisions.
- Open systems exchange energy and matter with their surroundings.
- Magnetic fields influence charged particle dynamics.
Purpose of the Study:
- Investigate Brownian particle properties in a fluctuating magnetic field.
- Analyze the impact of time-dependent magnetic fields on system dynamics.
- Explore phenomena like resonant activation and barrier crossing.
Main Methods:
- Studied a Brownian particle in a stationary state.
- Introduced a fluctuating magnetic field to create an open system.
- Analyzed the steady-state distribution function and mean first passage time.
Main Results:
- Steady-state distribution depends on damping, fluctuation intensity, and magnetic field parameters.
- Fluctuating magnetic fields can induce resonant activation.
- Observed giant enhancement of barrier crossing rates, contrasting with exponential divergence in typical colored noise systems.
- Identified potential breakdown of Arrhenius law and Kramers' turnover phenomenon.
Conclusions:
- Time-dependent magnetic fields significantly alter Brownian particle behavior in open systems.
- Fluctuating fields offer novel mechanisms for controlling particle dynamics and overcoming energy barriers.
- Findings challenge established theories and suggest new avenues for research in non-equilibrium statistical physics.
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