Three-dimensional spontaneous flow transition in a homeotropic active nematic

Pratley, Vincenzo J. (author), Caf, Enej (author), Ravnik, Miha (author), Alexander, Gareth P. (author)

Active nematics are driven, non-equilibrium systems relevant to biological processes including tissue mechanics and morphogenesis, and to active metamaterials in general. We study the three-dimensional spontaneous flow transition of an active nematic in an infinite slab geometry using a combination of numerics and analytics. We show that it is determined by the interplay of two eigenmodes – called S- and D-mode – that are unstable at the same activity threshold and spontaneously breaks both rotational symmetry and chiral symmetry. The onset of the unstable modes is described by a non-Hermitian integro-differential operator, which we determine their exponential growth rates from using perturbation theory. The S-mode is the fastest growing. After it reaches a finite amplitude, the growth of the D-mode is anisotropic, being promoted perpendicular to the S-mode and suppressed parallel to it, forming a steady state with a full three-dimensional director field and a well-defined chirality. Lastly, we derive a model of the leading-order time evolution of the system close to the activity threshold.

• Language: English
• Keywords: nematic fluids, active nematics
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FMF - Faculty of Mathematics and Physics
• Publication version: Version of Record
• Publication date: 13.04.2024
• Year: 2024
• Number of pages: 13 str.
• Numbering: Vol. 7, art. no. ǂ127
• PID: 20.500.12556/RUL-156067
• UDC: 532.5
• ISSN on article: 2399-3650
• DOI: 10.1038/s42005-024-01611-y
• COBISS.SI-ID: 194618883
• Publication date in RUL: 07.05.2024

PRATLEY, Vincenzo J., CAF, Enej, RAVNIK, Miha and ALEXANDER, Gareth P., 2024, Three-dimensional spontaneous flow transition in a homeotropic active nematic. Communications physics [online]. 2024. Vol. 7, no. 127. [Accessed 26 April 2025]. DOI 10.1038/s42005-024-01611-y. Retrieved from: https://repozitorij.uni-lj.si/IzpisGradiva.php?lang=eng&id=156067

Record is a part of a journal

• Title: Communications physics
• Shortened title: Commun. phys.
• Publisher: Springer Nature
• ISSN: 2399-3650
• COBISS.SI-ID: 2048602387

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.

Secondary language

• Language: Slovenian
• Keywords: nematske tekočine, aktivni nematiki