Forming a cube from a sphere with tetratic order

Abstract

Composed of square particles, the tetratic phase is characterised by a four-fold symmetry with quasi-long-range orientational order but no translational order. We construct the elastic free energy for tetratics and find a closed form solution for 1/4-disclinations in planar geometry. Applying the same covariant formalism to a sphere we show analytically that within the one elastic constant approximation eight +1/4-disclinations favor positions defining the vertices of a cube. The interplay between defect-defect interactions and bending energy results in a flattening of the sphere towards superspheroids with the symmetry of a cube.

main text + supplemental material; accepted for publication in PRL

References in corpus (3)

• Two-Dimensional Matter: Order, Curvature and Defects
• Nematic textures in spherical shells
• Theory and simulation of two-dimensional nematic and tetratic phases