Orientational Correlations in Active and Passive Nematic Defects

D J G Pearce; J Nambisan; P W Ellis; A Fernandez-Nieves; L Giomi

doi:10.1103/PhysRevLett.127.197801

Orientational Correlations in Active and Passive Nematic Defects

Phys Rev Lett. 2021 Nov 5;127(19):197801. doi: 10.1103/PhysRevLett.127.197801.

Authors

D J G Pearce^{1

2}, J Nambisan^{3

4}, P W Ellis⁵, A Fernandez-Nieves^{3

4

6}, L Giomi⁷

Affiliations

¹ Department of Mathematics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02142, USA.
² Departments of Biochemistry and Theoretical Physics, Université de Genéve, 1205 Genéve, Switzerland.
³ Department of Condensed Matter Physics, University of Barcelona, 08028 Barcelona, Spain.
⁴ School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332, USA.
⁵ John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, USA.
⁶ ICREA-Institucio Catalana de Recerca i Estudis Avancats, 08010 Barcelona, Spain.
⁷ Instituut-Lorentz, Universiteit Leiden, P.O. Box 9506, 2300 RA Leiden, Netherlands.

PMID: 34797140
DOI: 10.1103/PhysRevLett.127.197801

Abstract

We investigate the emergence of orientational order among +1/2 disclinations in active nematic liquid crystals. Using a combination of theoretical and experimental methods, we show that +1/2 disclinations have short-range antiferromagnetic alignment, as a consequence of the elastic torques originating from their polar structure. The presence of intermediate -1/2 disclinations, however, turns this interaction from antialigning to aligning at scales that are smaller than the typical distance between like-sign defects. No long-range orientational order is observed. Strikingly, these effects are insensitive to material properties and qualitatively similar to what is found for defects in passive nematic liquid crystals.