Abstract

Two methods that have been suggested for a fiber based all-optical demultiplexer are with a nonlinear optical loop-mirror (NOLM) [1] or to use four-wave mixing (FWM) [2]. The first or this methods have a theoretical maximum efficiency of 100 % and a rectangular, well defined switching window. With the second method, on the other hand, we show that more than 100% efficiency can be achieved. At the same time the switching window is highly dependent on longitudinal variations of the fiber zero-dispersion wavelength, λ₀. Two 10 GHz mode-locked external cavity lasers were used as pulse sources in our measurements. The signal was modulated at 10 Gbit/s and multiplexed optically to 20 Gbit/s, and its wavelength, λ_s, was a variable parameter in the experiment. The pump wavelength was fixed at λ_p=λ₀+0.5 nm to achieve phase-matching by compensating for nonlinearities [3].

© 1996 IEEE