In the thirty years since the installation of the first fiber optic data link, data rates in installed fiber links have risen from a few Mb/s to tens of Gb/s. In the laboratory, data rates in a single optical fiber have already reached tens of Tb/s. These data rates greatly exceed electronic processing rates, so researchers have turned to all-optical signal processing to achieve many basic network tasks, like wavelength conversion, packet switching, and data regeneration. As data rates increase, the impairments caused by propagation through the glass of optical fiber become worse. Chromatic dispersion causes the temporal broadening of optical bits during propagation, leading to interference between neighboring bits. Nonlinear effects, like the nonlinear index of refraction and four-wave mixing, can cause interference between neighboring wavelength channels. The interaction of dispersion and nonlinearities can lead to variations in the timing of bits and the appearance of optical energy where there had been none. All these effects make 1-bits and 0-bits difficult to distinguish. Today, these distortions are overcome by electronic regenerators. Optical data streams are converted to electrical signals, processed electronically, converted back to an optical signal, and returned to the optical network. In this way, regenerators prevent the accumulation of noise and prevent noise from contributing to the production of more noise. The electronic solution is costly because of the extra hardware required for optical to electrical to optical conversions and performs poorly because of the losses incurred by those conversions. In this thesis, we investigate two regenerators that restore the data quality of ON/OFF keyed data without a conversion of the data to the electrical domain.
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