Unique Solution of Short Pulse Propagation in Nonlinear Fiber Bragg Grating

In this study, a new numerical method is introduced to obtain the exact shape of output pulse in the chalcogenide fiber Bragg grating (FBG). A Gaussian pulse shape with 173 ps width is used as an input pulse for lunching to a 6.6 mm nonlinear FBG. Because of bistable and hysteresis nature of nonlinear FBG the time sequence of each portion of pulse is affected the shape of output pulse. So we divide the pulse to leading and trailing portion in time. By using bistability curve and Fourier transformation, the exact shape of output pulse is simulated. In comparison of non-unique solution for output pulse in the previous papers, the results of this study have an optional merit.