Structure of the dielectric tensor in nematic liquid crystals with topological charge

VAVELIUK, P.; MORAES, F.; FUMERON, S.; MARTINEZ MATOS, O.; CALVO, M. L.

JOURNAL OF THE OPTICAL SOCIETY OF AMERICA A-OPTICS IMAGE SCIENCE AND VISION - (Print)

OPTICAL SOC AMER

Año: 2010 vol. 27 p. 1466 - 1472

1084-7529

A q-plate is a stratified medium composed of a uniaxial nematic liquid crystal with an inhomogeneous orientation of the optical axis possessing a topological charge q , which looks promising as a switching device. This work reports an approach to diagonalizing the dielectric tensor in q-plates, giving a detailed study of nontrivial tensor coordinate transformations. The relationship between the diagonal dielectric tensor and the topological charge of the plate is established. From that, the dielectric tensor for a given q-plate can be explicitly calculated in a convenient frame, and hence the field propagation equations can be derived. These studies establish a theoretical basis that could further deepen the research on these particular structures for nonconventional manipulation of the light.