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arXiv · 1412.3521

Forming a cube from a sphere with tetratic order

O. V. Manyuhina·M. J. Bowick
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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.

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O. V. Manyuhina, M. J. Bowick. 2015-02-27. Forming a cube from a sphere with tetratic order. https://doi.org/10.1103/physrevlett.114.117801

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