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arXiv · 1111.4782

Unifying model of driven polymer translocation

Timo Ikonen·Aniket Bhattacharya·Tapio Ala-Nissila·Wokyung Sung
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Abstract

We present a Brownian dynamics model of driven polymer translocation, in which non-equilibrium memory effects arising from tension propagation (TP) along the cis side subchain are incorporated as a time-dependent friction. To solve the effective friction, we develop a finite chain length TP formalism, expanding on the work of Sakaue [Sakaue, PRE 76, 021803 (2007)]. The model, solved numerically, yields results in excellent agreement with molecular dynamics simulations in a wide range of parameters. Our results show that non-equilibrium TP along the cis side subchain dominates the dynamics of driven translocation. In addition, the model explains the different scaling of translocation time w.r.t chain length observed both in experiments and simulations as a combined effect of finite chain length and pore-polymer interactions.

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Timo Ikonen, Aniket Bhattacharya, Tapio Ala-Nissila, Wokyung Sung. 2012-04-18. Unifying model of driven polymer translocation. https://doi.org/10.1103/physreve.85.051803

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