English

Motile dislocations knead odd crystals into whorls

Soft Condensed Matter 2022-03-09 v2

Abstract

The competition between thermal fluctuations and potential forces is the foundation of our understanding of phase transitions and matter in equilibrium. Driving matter out of equilibrium allows for a new class of interactions which are neither attractive nor repulsive but transverse. The existence of such transverse forces immediately raises the question of how they interfere with basic principles of material self-organization. Despite a recent surge of interest, this question remains open. Here, we show that activating transverse forces by homogeneous rotation of colloidal units generically turns otherwise quiescent solids into a crystal whorl state dynamically shaped by self-propelled dislocations. Simulations of both a minimal model and a full hydrodynamics model establish the generic nature of the chaotic dynamics of these self-kneading polycrystals. Using a continuum theory, we explain how odd and Hall stresses conspire to destabilize chiral crystals from within. This chiral instability produces dislocations that are unbound by their self-propulsion. Their proliferation eventually leads to a crystalline whorl state out of reach of equilibrium matter.

Keywords

Cite

@article{arxiv.2102.03263,
  title  = {Motile dislocations knead odd crystals into whorls},
  author = {Ephraim S. Bililign and Florencio Balboa Usabiaga and Yehuda A. Ganan and Alexis Poncet and Vishal Soni and Sofia Magkiriadou and Michael J. Shelley and Denis Bartolo and William T. M. Irvine},
  journal= {arXiv preprint arXiv:2102.03263},
  year   = {2022}
}
R2 v1 2026-06-23T22:52:45.787Z