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arXiv · 1503.01966

Scaling regimes of a semi-flexible polymer in a rectangular channel

E. Werner·B. Mehlig
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Abstract

We derive scaling relations for the extension statistics and the confinement free energy for a semi-flexible polymer confined to a channel with a rectangular cross-section. Our motivation are recent numerical results [Gupta {\em et al.}, JCP {\bf 140} (2014) 214901] indicating that extensional fluctuations are quite different in rectangular channels compared to square channels. Our results are of direct relevance for interpreting current experiments on DNA molecules confined to nano-channels, as many experiments are performed for rectangular channels with large aspect ratios while theoretical and simulation results are usually obtained for square channels.

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E. Werner, B. Mehlig. 2015-03-06. Scaling regimes of a semi-flexible polymer in a rectangular channel. https://doi.org/10.1103/physreve.91.050601

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