Initially twisted pi cell fabricated using liquid crystal-silica colloidal dispersions.

We demonstrate an initially twisted pi cell fabricated by doping silica nanoparticles into the conventional pi cell. With AC high voltage, the director distortion of the liquid crystals (LCs) near the substrate surface creates a lifting force, which moves the silica nanoparticles toward the substrate surfaces. The accumulated silica nanoparticles on the substrate surfaces stabilize the LCs at the twisted pi state when the AC high voltage is turned off. The formed twisted pi state is permanent. The operation voltage and the response time of the initially twisted pi cell are less than those of the conventional pi cell.