Motion of a polymer globule with Vicsek-like activity: from super-diffusive to ballistic behavior

ABSTRACT

Via molecular dynamics simulation with Langevin thermostat we study the structure and dynamics of a flexible bead-spring active polymer model after a quench from good to poor solvent conditions. The self propulsion is introduced via a Vicsek-like alignment activity rule which works on each individual monomer in addition to the standard attractive and repulsive interactions among the monomeric beads. We observe that the final conformations are in the globular phase for the passive as well as for all the active cases. By calculating the bond length distribution, radial distribution function, etc., we show that the kinetics and also the microscopic details of these pseudo equilibrium globular conformations are not the same in all the cases. Moreover, the center-of-mass of the polymer shows a more directed trajectory during its motion and the behavior of the mean-squared-displacement gradually changes from super-diffusive to ballistic under the influence of the active force in contrast to the diffusive behavior in the passive case.

KEYWORDS:

• Active matter
• polymer

Acknowledgments

This project was funded by the Deutsche Forschungsge–meinschaft (DFG, German Research Foundation) under Grant No. 189 853 844–SFB/TRR 102 (Project B04). It was further supported by the Deutsch-Französische Hochschule (DFH-UFA) through the Doctoral College “${\mathbb{L}}^4$” under Grant No. CDFA-02-07, the Leipzig Graduate School of Natural Sciences “BuildMoNa”, and the EU COST programme EUTOPIA under Grant No. CA17139.

Additional information

Funding

This work was supported by the Deutsche Forschungsge–meinschaft [Grant No. 189 853 844--SFB/TRR 102 (Project B04)].