Title: Parametric Devices for Ultra-high-speed Systems
Speaker: Professor Prem Kumar
Speaker Info: Northwestern U.
Almost instantaneous response of optical-parametric processes make them attractive for device applications in ultra-high-speed systems. A workhorse device is a nonlinear Sagnac interferometer, or a nonlinear loop mirror, which can be configured to perform many diverse functions including optical switching, amplification, demultiplexing, and regeneration. As a parametric amplifier, when used in the phase-sensitive configuration, such a device preserves the signal-to-noise ratio, thus making it an ideal amplifier with a 0 dB noise figure. Such amplifiers can be built from standard fibers with use of the nonlinear refractive index. When used with solitons, such amplifiers can reduce the Gordon-Haus timing jitter without the need for extra filters, curtail the Raman-effect induced frequency shift, and suppress the soliton-soliton interactions. Pulses can propagate over long distances without accumulating dispersive radiation generated during the amplification and decay between the amplifiers. In this talk I will overview the above advantages of the parametric amplifiers and show how the last property can be exploited for long-term storage of a picosecond-pulse packet in a fiber buffer. Time permitting, I will also present our recent results pertaining to the bit-error rate degradation caused by Sagnac interferometers when they are configured as optical regenerators.Date: Friday, October 31, 1997