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arXiv · 1205.4165

Simulating flexible polymers in a potential of randomly distributed hard disks

Sebastian Schöbl·Johannes Zierenberg·Wolfhard Janke
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Abstract

We perform equilibrium computer simulations of a two-dimensional pinned flexible polymer exposed to a quenched disorder potential consisting of hard disks. We are especially interested in the high-density regime of the disorder, where subtle structures such as cavities and channels play a central role. We apply an off-lattice growth algorithm proposed by Garel and Orland [J. Phys. A 23, L621 (1990)], where a distribution of polymers is constructed in parallel by growing each of them monomer by monomer. In addition we use a multicanonical Monte Carlo method in order to cross-check the results of the growth algorithm. We measure the end-to-end distribution and the tangent-tangent correlations. We also investigate the scaling behavior of the mean square end-to-end distance in dependence of the monomer number. While the influence of the potential in the low-density case is merely marginal, it dominates the configurational properties of the polymer for high densities.

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Sebastian Schöbl, Johannes Zierenberg, Wolfhard Janke. 2012-05-18. Simulating flexible polymers in a potential of randomly distributed hard disks. https://doi.org/10.1103/physreve.84.051805

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