Analysis of bistable switching and dynamic characteristics of tapered nonlinear Bragg gratings based on the time-domain transfer matrix method

Standing from the coupled mode theory, by utilizing the time-domain transfer matrix method, the bistable switching and dynamic characteristics of nonlinear Bragg gratings (NLBG) can be analyzed numerically. The results show: under steady case, various tapered factor has a different effect on the threshold switching energy and also positive and negative taper can cause the response of optical isolator in NLBG. On the other hand, with the continuous wave taken into consideration, the periodic self-pulsation may emerge easily under the dynamic conditions in NLBG. As the input power is increased to the critical intensity, the self-pulsation transform into the chaos. For the certain tapered cause, the pulsation width and the frequency of the self-pulsation will reduce with increase coupling coefficient, but the output state will transform into relaxation damped oscillation when the coupling coefficient reaches certain value.