Nematic liquid crystals (NLC) possess very broadband [400 nm to 20 microns] birefringence and transparency, and extraordinarily large optical nonlinearit [1]. There have been attempts to infiltrate photonic crystals with liquid crystals to fabricate tunable devices. These attempts are plaqued with serious surface alignment problems. In this paper, we report a novel approach of directly writing permanent [but electrically switchable] 2-D holographic gratings on pure liquid crystalline structures fabricated with well established alignment surfaces. Our theoretical analysis shows that such structures exhibit tunable bandgap, and will also enable super-prism beam steering effects [4,5].
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