Improvement of switching dynamics of nematic liquid crystals for phase modulation and integrated optic applications

The relaxation dynamics of nematic liquid crystal (LC) molecules limit the entire switching characteristic of phase modulators and switches. We present preliminary results of parallel alignment of nematic LCs embedded in UV-curable polymer sub domains using magnetic fields. A fine magnetic powder is used to trigger LC molecules for parallel orientation by applying an external magnetic field. The induced alignment could be fixed after UV-curing. This configuration allows conventional phase modulation at higher switching speeds by decreasing the relaxation time caused by the domain like confinement. Further advantages of our method are the abdication of any mechanical treatment of the LC cells and adjustable pretilt. The investigated set of parameters and measurements are presented and a novel concept of integrated optic beam steerer is proposed.