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Stochastic resonance in the Fermi-Pasta-Ulam chain
George Miloshevich1, Ramaz Khomeriki, Stefano Ruffo
1Physics Department, Tbilisi State University, 0128 Tbilisi, Georgia.
Physical Review Letters
|March 5, 2009
Summary
Stochastic resonance in a damped beta-Fermi-Pasta-Ulam chain is observed. Increasing noise intensity causes resonant energy response, with multiple peaks indicating stochastic resonance due to state transitions.
Area of Science:
- Nonlinear dynamics
- Statistical physics
- Condensed matter physics
Background:
- The Fermi-Pasta-Ulam chain is a fundamental model in nonlinear dynamics.
- Understanding energy transport and response to external stimuli is crucial.
- Stochastic resonance is a phenomenon where noise enhances signal detection.
Purpose of the Study:
- To investigate stochastic resonance in a damped beta-Fermi-Pasta-Ulam chain under external driving and noise.
- To analyze the system's energy response as a function of noise intensity.
- To explain the origin of multiple peaks in the signal-to-noise ratio.
Main Methods:
- Numerical simulations of a damped beta-Fermi-Pasta-Ulam chain.
- Analysis of the system's energy response to driving frequency and noise intensity.
- Semicontinuum approximation to identify stable and metastable states.
Main Results:
- The system's energy exhibits a resonant response to the modulating frequency of the forcing signal with increasing noise intensity.
- Multiple peaks were observed in the signal-to-noise ratio, confirming stochastic resonance.
- The presence of multiple peaks is attributed to transitions between numerous stable and metastable states.
Conclusions:
- Stochastic resonance is a significant phenomenon in this driven nonlinear system.
- The complex behavior, including multiple resonance peaks, arises from the system's rich state landscape.
- Transitions between discrete states are the underlying mechanism driving stochastic resonance in this model.
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