@article {142306, title = {Dynamic clustering of active rings}, journal = {Phys. Rev. Research}, volume = {6}, year = {2024}, month = {02/2024}, abstract = {

A collection of rings made of active Brownian particles (ABPs) for different packing fractions and activities is investigated using computer simulations. We show that active rings display an emergent dynamic clustering instead of the conventional motility-induced phase separation (MIPS) as in the case of collection of ABPs. Surprisingly, increasing packing fraction of rings exhibits a nonmonotonicity in the dynamics due to the formation of a large number of small clusters. The conformational fluctuations of the polymers suppress the usual MIPS exhibited by ABPs. Our findings demonstrate how the motion of a collection of rings is influenced by the interplay of activity, topology, and connectivity.

}, doi = {10.1103/PhysRevResearch.6.L012038}, author = {Theeyancheri, Ligesh and Chaki, Subhasish and Bhattacharjee, Tapomoy and Chakrabarti, Rajarshi} } @article {131292, title = {Active dynamics of linear chains and rings in porous media.}, journal = {J Chem Phys}, volume = {159}, year = {2023}, month = {2023 Jul 07}, abstract = {

To understand the dynamical and conformational properties of deformable active agents in porous media, we computationally investigate the dynamics of linear chains and rings made of active Brownian monomers. In porous media, flexible linear chains and rings always migrate smoothly and undergo activity-induced swelling. However, semiflexible linear chains though navigate smoothly, shrink at lower activities, followed by swelling at higher activities, while semiflexible rings exhibit a contrasting behavior. Semiflexible rings shrink, get trapped at lower activities, and escape at higher activities. This demonstrates how activity and topology interplay and control the structure and dynamics of linear chains and rings in porous media. We envision that our study will shed light on understanding the mode of transport of shape-changing active agents in porous media.

}, issn = {1089-7690}, doi = {10.1063/5.0148744}, author = {Theeyancheri, Ligesh and Chaki, Subhasish and Bhattacharjee, Tapomoy and Chakrabarti, Rajarshi} } @article {115812, title = {Migration of active rings in porous media.}, journal = {Phys Rev E}, volume = {106}, year = {2022}, month = {2022 Jul}, pages = {014504}, abstract = {

Inspired by how the shape deformations in active organisms help them to migrate through disordered porous environments, we simulate active ring polymers in two-dimensional random porous media. Flexible and inextensible active ring polymers navigate smoothly through the disordered media. In contrast, semiflexible rings undergo transient trapping inside the pore space; the degree of trapping is inversely correlated with the increase in activity. We discover that flexible rings swell while inextensible and semiflexible rings monotonically shrink upon increasing the activity. Together, our findings identify the optimal migration of active ring polymers through porous media.

}, issn = {2470-0053}, doi = {10.1103/PhysRevE.106.014504}, author = {Theeyancheri, Ligesh and Chaki, Subhasish and Bhattacharjee, Tapomoy and Chakrabarti, Rajarshi} }