光纤光栅传输矩阵研究

利用模耦合理论给出并分析了一般坐标系下相移布喇格光纤光栅中的传输矩阵及其特性,所给出的传输矩阵具有分段不变性,而且不能被分解为一个矩阵和一个相移矩阵的乘积.利用该传输矩阵可以研究均匀、相移、啁啾、超结构等光纤光栅及光栅的级联等.计算了相移光栅的反射谱和相移量的关系,以及两个光栅级联时的反射谱.结果表明,同样相移量时的反射谱和已有文献不同,两个光栅级联时,也不同于已有文献,各自的谐振波长与光栅的级联没有关系.

Investigation of the Transfer Matrix of the Fiber Gratings

Transfer matrix plays an important role in theoretical investigation of the fiber gratings,which is not the same as each other in different references.So it is not convenient for further investigation and application.The transfer matrix of the fiber Bragg gratings in general reference frame is derived from the coupled mode theory and its characteristics are analyzed.The transfer matrix is identical when the fiber grating is separated into several segments,and it can′t be divided as the product of two matrixes, one of which is the phase shifted matrix.The characteristics of the uniform,phased-shifted,chirped and superstructure and cascaded fiber gratings can be investigated by using the matrix.The phase shifted fiber gratings are analyzed and the relation between the spectrum and the shifted phases.The spectrum are not same as that given in the references when having the same shifted phase.When two fiber Bragg gratings are cascaded,the characteristics are investigated and it shows that both of the resonant wavelength have no relation with the cascade of the fiber gratings.