Single Harmonically Driven Electroabsorption Modulator for OTDM Demultiplexing

Optical demultiplexing from 160 Gbit/s to 10 Gbit/s in a single lumped, electrically driven electroabsorption modulator (EAM) is experimentally presented. A quantum-dash Fabry-Pèrot mode-locked-laser is used to sub-harmonically extract a clock signal from the 160 Gbit/s data stream. A drive signal consisting of a series of harmonics of the recovered clock signal enables error-free demultiplexing of all channels in a 160 Gbit/s single-polarization optical time division multiplexing (OTDM) signal. This technique is quasi-analytically compared with the conventional approach of cascading two EAMs when performing 160 Gbit/s to 10 Gbit/s demultiplexing. The analysis reveals that using a single, harmonically driven EAM can result in lower penalties with respect to both degradations of the extinction ratio and width of pulses used in the OTDM signal.