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Translocation dynamics of a short polymer driven by an oscillating force
Nicola Pizzolato1, Alessandro Fiasconaro, Dominique Persano Adorno
1Dipartimento di Fisica e Chimica, Università di Palermo and CNISM, Viale delle Scienze edificio 18, I-90128 Palermo, Italy.
The Journal of Chemical Physics
|February 15, 2013
Summary
We investigated polymer translocation through a pore in a noisy environment. We found that an oscillating force can speed up translocation, demonstrating resonant activation, a phenomenon that minimizes translocation time.
Area of Science:
- Polymer Physics
- Statistical Mechanics
- Soft Matter Physics
Background:
- Polymer translocation through nanopores is crucial for biological processes and nanotechnology.
- Understanding the factors influencing translocation dynamics, such as external forces and noise, is essential.
- Existing models often simplify the complex interactions and energy landscapes involved.
Purpose of the Study:
- To investigate the translocation dynamics of a short polymer driven by an oscillating force in a noisy environment.
- To explore the influence of polymer length and driving force frequency on translocation time.
- To identify and characterize phenomena like resonant activation in polymer translocation.
Main Methods:
- Numerical investigation using a Langevin equation in a 2D domain.
- Modeling polymer-pore interaction with a phenomenological cubic potential.
- Analysis of mean first translocation time as a function of polymer length and driving frequency.
Main Results:
- Mean translocation time exhibits non-monotonic behavior with polymer length, showing a minimum.
- Translocation time increases monotonically with polymer length for longer chains.
- A minimum in translocation time was observed as a function of oscillating force frequency, indicating resonant activation.
Conclusions:
- The study provides evidence for resonant activation in polymer translocation dynamics.
- The phenomenon of resonant activation is robust and maintained across different noise intensities.
- Optimizing driving force frequency can significantly reduce polymer translocation time.
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