Self-propulsion of active droplets without liquid-crystalline order

Singh, Rajesh; Tjhung, Elsen; Cates, Michael E.

Abstract

The swimming of cells, far from any boundary, can arise in the absence of long-range liquid-crystalline order within the cytoplasm, but simple models of this effect are lacking. Here, we present a two-dimensional model of droplet self-propulsion involving two scalar fields, representing the cytoplasm and a contractile cortex. An active stress results from coupling between these fields; self-propulsion results when rotational symmetry is spontaneously broken. The swimming speed is predicted, and shown numerically, to vary linearly with the activity parameter and with the droplet area fraction. The model exhibits a Crowley-like instability for an array of active droplets.

Citation

Singh, R., Tjhung, E., & Cates, M. E. (2020). Self-propulsion of active droplets without liquid-crystalline order. Physical Review Research, 2(3), Article 032024(R). https://doi.org/10.1103/physrevresearch.2.032024

• Journal Article Type: Article
• Acceptance Date: Jul 13, 2020
• Online Publication Date: Aug 23, 2020
• Publication Date: 2020
• Deposit Date: Sep 14, 2021
• Publicly Available Date: Sep 14, 2021
• Journal: Physical Review Research
• Electronic ISSN: 2643-1564
• Publisher: American Physical Society
• Peer Reviewed: Peer Reviewed
• Volume: 2
• Issue: 3
• Article Number: 032024(R)
• DOI: https://doi.org/10.1103/physrevresearch.2.032024
• Public URL: https://durham-repository.worktribe.com/output/1241465