Diffraction of light by topological defects in liquid crystals

Abstract

Light scattering due to hedgehog-like and linear disclination topological defects in a nematic liquid crystal has been studied. Light propagation close to such defects appears to be a metric equivalent to the spatial element of the global monopole and cosmic string geometries. Using a metric approach, the amplitude of the scattering and the differential and total scattering cross section have been obtained for the hedgehog defect in terms of the characteristic parameters of a liquid crystal. In the case of disclination, a cylindrical partial wave method has been developed. Applying the results of earlier studies, we have also examined the influence of temperature on the localisation of the diffraction patterns.

Keywords:

• geometrical theory
• analogue model
• Fermat's principle
• extraordinary index
• metric marifold
• Riemannian
• tensor

Acknowledgements

This study was supported in part by INCT–CX and CAPES (PROCAD).