Abstract

Macroscopic systems under the influence of injection, dissipation of energy and matter usually exhibit coexistence of different states [1]. Out of equilibrium systems show domain walls between different equilibria. These walls, depending on the type of connected equilibria, exhibit a rich spatiotemporal dynamics [2]. In a bistable isotropic system, one expects a finite disturbance on a less favourable state can generates two counter propagative fronts with the same speed, giving appearance of the most stable one. Notwithstanding, we have observed that perturbations of an Ising type walls in nematic liquid crystals with reflection symmetry generate two asymmetric counter propagative fronts [Fig. 1(a)]. Indeed, the speed and the shape of each front is different. It is worthy to note that the perturbations are generated by the presence of glass spheres inside the liquid crystal sample.

© 2015 IEEE