The Coil-Globule transition in self-avoiding active polymers

TL;DR

This study uses numerical simulations to analyze how active forces influence the coil-globule transition in self-avoiding polymers, revealing that active fluctuations can be effectively modeled by temperature rescaling.

Contribution

It introduces a method to determine the coil-globule transition in active polymers and shows that active fluctuations can be captured by a simple temperature rescaling.

Findings

Active forces shift the coil-globule transition point.

A temperature rescaling qualitatively captures the effect of activity.

Active pressure effects may be similar to those in active particle suspensions.

Abstract

We perform numerical simulations of an active fully flexible self-avoiding polymer as a function of the quality of the embedding solvent described in terms of an effective monomer-monomer interaction. Specifically, by extracting the Flory exponent of the active polymer under different conditions, we are able to pin down the location of the coil-globule transition for different strength of the active forces. Remarkably, we find that a simple rescaling of the temperature is capable of qualitatively capture the dependence of the $\Theta$-point of the polymer with the amplitude of the active fluctuations. We discuss the limits of this mapping, and suggest that a negative active pressure between the monomers, not unlike the one that has already been found in suspensions of active hard spheres, may also be present in active polymers.