The advance of polarization control method to ultraviolet-written Bragg gratings

A flexible and simple method for UV writing of Bragg gratings and polarization control method,is presented.The method is based on a phase shift between the refractive-index modulation profiles induced by s and p polarization of UV light.The modulation strength is able to be controlled and phase shifts are induced by changing the ratio of UV intensity in the two polarizations.Characteristics of spectrum of two written gratings are analysed,in good agreement with theoretical predictions.