We use Langevin dynamics simulations to study dynamical behavior of a dense planar layer of active semiflexible filaments. Using the strength of active force and the thermal persistence length as parameters, we map a detailed phase diagram and identify several nonequilibrium phases in this system. In addition to a slowly flowing melt phase, we observe that, for sufficiently high activity, collective flow accompanied by signatures of local polar and nematic order appears in the system. This state is also characterized by strong density fluctuations. Furthermore, we identify an activity-driven crossover from this state of coherently flowing bundles of filaments to a phase with no global flow, formed by individual filaments coiled into rotating spirals. This suggests a mechanism where the system responds to activity by changing the shape of active agents, an effect with no analog in systems of active particles without internal degrees of freedom.
|Number of pages
|Physical Review. E, Statistical, Nonlinear and Soft Matter Physics
|Early online date
|12 Feb 2018
|Published - Feb 2018
Bibliographical noteAcknowledgements. We acknowledge financial support from EPSRC (EP/M009599/1) and BBSRC (BB/N009789/1 and BB/N009150/1). We thank A. Das
for comments on the manuscript. KRP would like to thank A. Maitra and S. Saha for many useful discussions.
- Langevin Dynamic Simulations
- Active filaments
- Active semiflexible filaments