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Published on: March 16, 2020
Dynamics of an anchored polymer molecule under an oscillating force
A K Chattopadhyay1, D Marenduzzo
1Dipartimento di Fisica G. Galilei, Universitá degli Studi di Padova, via Marzolo 8, 35131 Padua, Italy.
Physical Review Letters
|March 16, 2007
Summary
As polymer stiffness increases, its dynamics shift from predictable cycles to complex, unpredictable motion. This aperiodic behavior in stiffer polymers exhibits characteristics of chaos.
Area of Science:
- Polymer physics
- Nonlinear dynamics
- Computational physics
Background:
- Polymers exhibit complex behaviors influenced by stiffness and external forces.
- Understanding polymer dynamics is crucial for materials science and nanotechnology.
- Oscillatory forcing can induce non-trivial responses in polymeric systems.
Purpose of the Study:
- To investigate the dynamic response of a polymer with variable stiffness.
- To analyze the effect of oscillatory forcing on pinned or grafted polymers.
- To identify transitions in polymer dynamics related to stiffness.
Main Methods:
- Stochastic simulations were employed to model polymer dynamics.
- The polymer was subjected to oscillatory forcing at an intermediate point.
- Analytical arguments were developed for specific polymer configurations (2D grafted).
Main Results:
- A crossover in dynamics was observed as polymer stiffness increased.
- The system transitioned from a periodic limit cycle to aperiodic dynamics.
- Stiffer polymers displayed aperiodic dynamics with signatures of chaos.
Conclusions:
- Polymer stiffness is a critical parameter governing its dynamic behavior.
- Increased stiffness can lead to a transition from periodic to chaotic dynamics.
- The findings provide insights into the complex behavior of polymers under external forcing.
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