Field analysis based on the smoothly deformed Bragg fiber

A new kind of smoothly deformed Bragg fiber structure has been proposed in this paper, and the mode field characteristics about this fiber have been analyzed. By comparing the field at different coordinates along the propagation direction, the evolution of the field for the elliptical transverse faces and the circular one is obtained. The method has also been used to detect the behavior of the elliptical Gaussian beam. This research method can be used to analyze the thermal deformation of fiber.