Characterization of the vortex-pair interaction law and nonlinear mobility effects

R. Barboza, T. Sauma, U. Bortolozzo, G. Assanto, M.G. Clerc and S. Residori

New J. Phys. 15 (1), 013028 (2013)

Abstract:

Employing nematic liquid crystals in a homeotropic cell with a photosensitive wall, dissipative vortex pairs are selectively induced by external illumination and the interaction law is characterized for pairs of opposite topological charges. Contrary to the phenomenological fit with a force inversely proportional to the distance, the data provide evidence that nonlinear mobility effects must be taken into account. The observations lead to a reconciliation of experiments with theory.