Defects in vertically vibrated monolayers of cylinders

Abstract

We analyse liquid-crystalline ordering in vertically vibrated monolayers of cylinders confined in a circular cavity. Short cylinders form tetratic arrangements with C${}_4$ symmetry. This symmetry, which is incompatible with the geometry of the cavity, is restored by the presence of four point defects with total topological charge $+4$. Equilibrium Monte Carlo simulations predict the same structure. A new method to measure the elastic properties of the tetratic medium is developed which exploits the clear similarities between the vibrated dissipative system and the thermal equilibrium system. Our observations open up a new avenue to investigate the formation of defects in response to boundary conditions, an issue which is very difficult to realize in colloidal or molecular systems.

arXiv comment7 pages, 4 figures

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Cited by in corpus (6)

• Domain walls in vertically vibrated monolayers of cylinders confined in annuli
• Reduced-variance orientational distribution functions from torque sampling
• Effect of clustering on the orientational properties of a fluid of hard right isosceles triangles
• In pursuit of the tetratic phase in hard rectangles
• Exotic liquid crystalline phases in monolayers of vertically vibrated granular particles
• Failure of standard density functional theory to describe the phase behavior of a fluid of hard right isosceles triangles