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Theory of beam coupling in a hybrid photorefractive-liquid crystal cell

QinetiQ, Photonics and Displays, St. Andrew’s Road, Great Malvern, Worcestershire WR14 3PS, UK; DSTL, St. Andrew’s Road, Great Malvern, Worcestershire WR14 3PS, UK
Optics Communications (Impact Factor: 1.54). 03/2004; DOI: 10.1016/j.optcom.2003.12.050

ABSTRACT A theory of beam coupling in a hybrid photorefractive liquid crystal cell is developed. The hybrid cell consists of layers of undoped nematic liquid crystal contained within wafers of photorefractive crystal or photoconductors. Reorientation of the liquid crystal is induced by the evanescent component of the space charge field propagating from the photorefractive layers, leading to a modulation of the liquid crystal refractive index. Using coupled wave theory, an analytic solution is obtained for the small signal gain in good agreement with previously published experimental work.

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