All-optical loadable and erasable fiber storage buffer based on parametric nonlinearity in fiber

Optical storage devices are envisaged to play a key role in high speed optical networks. They would be required to facilitate advanced information processing in future photonic networks. Towards this end an all-optical fiber storage buffer which uses a phase-sensitive amplifier (PSA) is presented. PSAs exhibit several useful properties such as 0 dB noise figure and low soliton timing jitter. These two properties fulfill the two main requirements of an optical memory, i.e., maintaining timing of pulses and ensuring stability of zeros. The 0 dB noise figure ensures that noise in the zero does not build up, whereas the low timing jitter prevents pulses from drifting away from the assigned time slots. Here the PSA is implemented as a nonlinear fiber Sagnac interferometer (NFSI).; Apart from maintenance of data packets, an optical buffer requires loading. This operation is accomplished by using the NFSI as a switch, which is activated only when both data and pump are present. The storage buffer is loaded using the technique of cross-phase modulation (XPM). Externally generated data packets are switched in a phase-insensitive manner by wavelength-induced XPM.; Once external data is loaded and stored for a given duration in the buffer, it maybe required to erase the buffer. This is achieved by incorporating a nonlinear optical loop mirror as an optical switch within the buffer. Cross-phase modulation within the nonlinear optical loop mirror helps to unload the buffer.; A fiber-optic device capable of storing picosecond data pulse-packets by utilizing the mechanisms of phase-sensitive parametric amplification and phase-insensitive XPM is the subject of this dissertation. Storage is achieved by utilizing the parametric nonlinearity in standard fiber.; Storage results obtained with this device at lower data rates will be presented first and then its capability is extended to higher data rates of 1 Gb/s, more compatible with present optical networks. Storage has been observed for times up to 1 ms in both cases. Finally results on erasure of the buffer employing the nonlinear optical loop mirror are presented.