All - optical Signal Processing Using Nonlinear Periodic Structures : A Study of Temporal

All-optical Signal Processing Using Nonlinear Periodic Structures: A Study of Temporal Response Winnie Ning Ye Master of Applied Science Graduate Department of Electrical and Computer Engineering University of Toronto 2002 This work presents the first time-domain analysis of pulse propagation through stable, balanced nonlinear periodic structures, with a focus on design towards all-optical signal processing applications. The propagation dynamics of ultrashort pulses in the nonlinear structures with varying grating lengths and linear grating strengths are investigated. In the absence of a linear grating, with two adjacent layers of nonlinear materials (n1,2 = 1.50 ± (2.5 × 10−12 cm/GW)Iin), the pulse-bandwidth-dependent limiting behavior is investigated. The output peak intensity of a 600 fs input pulse is found to be limited to 1.2 GW/cm for a 290 μm-long device. In the presence of a linear grating, Sand N-curve transfer characteristics are observed. A 720 μm-long device with a 0.01 out-ofphase linear grating (i.e., n1,2 = (1.50∓ 0.01)± (2.5× 10−12 cm/GW)Iin), compresses a pulse down to 12% of its original width. The results reported in this work point to the promise of such devices in signal processing.