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arXiv · 0910.1501

Plectoneme creation reduces the rotational friction of a polymer

Hirofumi Wada·Roland R. Netz
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Abstract

The torsional dynamics of a semiflexible polymer with a contour length $L$ larger than its persistence length L_p that is rotated at fixed frequency omega_0 at one end is studied by scaling arguments and hydrodynamic simulations. We find a non-equilibrium transition at a critical frequency omega_*: In the linear regime, omega_0 < omega_*, axial spinning is the dominant dissipation mode. In the non-linear regime, omega_0 > omega_*, the twist-dissipation mode involves the continuous creation of plectonemes close to the driven end and the rotational friction is substantially reduced.

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Hirofumi Wada, Roland R. Netz. 2009-10-08. Plectoneme creation reduces the rotational friction of a polymer. https://doi.org/10.1209/0295-5075/88/49901

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