Translocation time of periodically forced polymer chains

TL;DR

This paper investigates how a periodically driven linear potential affects the translocation time of a unidimensional polymer chain, revealing oscillations, a minimum, and scaling laws, with insights into resonance phenomena and thermal effects.

Contribution

It demonstrates the existence of oscillations and a minimum in translocation time due to external forcing, and establishes a simple relationship between optimal frequency and translocation time.

Findings

Oscillations in translocation time due to external frequency.

A clear minimum in translocation time at a specific frequency.

L^2 scaling of translocation time with polymer length.

Abstract

We show the presence of both a minimum and clear oscillations in the frequency dependence of the translocation time of a polymer described as a unidimensional Rouse chain driven by a spatially localized oscillating linear potential. The observed oscillations of the mean translocation time arise from the synchronization between the very mean translocation time and the period of the external force. We have checked the robustness of the frequency value for the minimum translocation time by changing the damping parameter, finding a very simple relationship between this frequency and the correspondent translocation time. The translocation time as a function of the polymer length has been also evaluated, finding a precise $L^2$ scaling. Furthermore, the role played by the thermal fluctuations described as a Gaussian uncorrelated noise has been also investigated, and the analogies with the resonant activation phenomenon are commented.