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arXiv · 2004.04368

Conformation and dynamics of a self-avoiding active flexible polymer

Shalabh K. Anand·Sunil P. Singh
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Abstract

We investigate conformations and dynamics of a polymer considering its monomers to be active Brownian particles. This active polymer shows very intriguing physical behavior which is absent in an active Rouse chain. The chain initially shrinks with active force, which starts swelling on further increase in force. The shrinkage followed by swelling is attributed purely to excluded-volume interactions among the monomers. In the swelling regime, chain shows a cross-over from the self-avoiding behavior to Rouse-behavior with scaling exponent $\nu_a \simeq 1/2$ for end-to-end distance. The non-monotonicity in the structure is analysed through various physical quantities specifically, radial distribution function of monomers, scattering time, as well as various energy calculations. The chain relaxes faster than the Rouse chain in the intermediate force regime, with a cross-over in variation of relaxation time at large active force as given by a power-law $\tau_r \sim Pe^{-4/3}$ (P e is P\'eclet number).

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Shalabh K. Anand, Sunil P. Singh. 2020-04-09. Conformation and dynamics of a self-avoiding active flexible polymer. https://doi.org/10.1103/physreve.101.030501

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