Effective elasticity of a flexible filament bound to a deformable cylindrical surface

TL;DR

This paper demonstrates through simulations that a flexible filament bound to a deformable cylindrical surface can develop a persistent helical shape, with its pitch controlled by surface properties and binding energy.

Contribution

It introduces a novel mechanism where surface elasticity induces macroscopic persistence length and helical conformation in flexible filaments.

Findings

Filament acquires a helical shape due to surface elasticity.

Helical pitch is determined by surface mechanical properties.

Binding energy influences the filament's conformation.

Abstract

We use numerical simulations to show how a fully flexible filament binding to a deformable cylindrical surface may acquire a macroscopic persistence length and a helical conformation. This is a result of the nontrivial elastic response to deformations of elastic sheets. We find that the filament's helical pitch is completely determined by the mechanical properties of the surface, and can be tuned by varying the filament binding energy. We propose simple scaling arguments to understand the physical mechanism behind this phenomenon and present a phase diagram indicating under what conditions one should expect a fully flexible chain to behave as a helical semi-flexible filament. Finally, we discuss the implications of our results.