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Forming a cube from a sphere with tetratic order
1Physics Department, Syracuse University, Syracuse, New York 13244, USA.
Physical Review Letters
|April 4, 2015
Summary
The tetratic phase, composed of square particles, exhibits fourfold symmetry. Researchers found that eight +1/4 disclinations on a sphere arrange into a cube
Area of Science:
- Soft matter physics
- Liquid crystals
- Materials science
Background:
- The tetratic phase features square particles with fourfold symmetry.
- It shows quasi-long-range orientational order but lacks translational order.
Purpose of the Study:
- To construct the elastic free energy for tetratic phases.
- To analyze the behavior of disclinations in planar and spherical geometries.
Main Methods:
- Developed a covariant formalism to model elastic free energy.
- Derived a closed-form solution for ±1/4 disclinations in planar geometry.
- Applied the formalism to a sphere under the one elastic constant approximation.
Main Results:
- Identified eight +1/4 disclinations on a sphere, positioning them at the vertices of a cube.
- Demonstrated that defect interactions and bending energy cause sphere flattening into cube-symmetric superspheroids.
Conclusions:
- The study provides analytical insights into the defect behavior in tetratic phases.
- Predicts the formation of cube-like superspheroids due to elastic and defect energies.
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