Electrically induced transformation of cholesteric droplets under homeotropic boundary conditions

Cholesteric droplets under homeotropic boundary conditions demonstrate a rich variety of possible orientational structures. We have implemented electrically controlled switching of such droplets between two classes of stable states: i) structures with cylindrical cholesteric layers and ii) layer-like structures with one or more λ^+1/2-disclinations. Structure relaxation after switching off the voltage proceeded via the fast (less than 1 s), the slow (more than 1 s), and the stabilization stages (∼10 hours). We investigated intermediate long-lived metastable states occurring in the relaxation process and explained the formation of various structures in cholesteric droplets. The fast and the slow stages of relaxation were found to be sensitive to the voltage reduction regime. We have determined the combinations of droplet size and voltage reduction regimes leading to the two types of structures after relaxation.