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arXiv · 2403.05914

Migration and separation of polymers in non-uniform active baths

Pietro Luigi Muzzeddu·Andrea Gambassi·Jens-Uwe Sommer·Abhinav Sharma
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Abstract

Polymer-like structures are ubiquitous in nature and synthetic materials. Their configurational and migration properties are often affected by crowded environments leading to non-thermal fluctuations. Here, we study an ideal Rouse chain in contact with a non-homogeneous active bath, characterized by the presence of active self-propelled agents which exert time-correlated forces on the chain. By means of a coarse-graining procedure, we derive an effective evolution for the center of mass of the chain and show its tendency to migrate towards and preferentially localize in regions of high/low bath activity depending on the model parameters. In particular, we demonstrate that an active bath with non-uniform activity can be used to separate efficiently polymeric species with different lengths and/or connectivity.

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Pietro Luigi Muzzeddu, Andrea Gambassi, Jens-Uwe Sommer, Abhinav Sharma. 2024-03-09. Migration and separation of polymers in non-uniform active baths. https://arxiv.org/abs/2403.05914

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