Abstract: A device and method for reducing amplified Rayleigh backscatter at a Raman pump. A pump assembly for an optical amplifier includes a set of pump radiation sources for Raman pumping an optical transmission span. Each pump radiation source is adapted to produce radiation having a pump wavelength and a pump power. The optical transmission span is adapted to provide Raman amplification of an optical data signal when pumped by the set of pump radiation sources. At least one optical isolator is selectively located between at least one selected pump radiation source and the optical transmission span to reduce amplified Rayleigh backscatter at the pump wavelength of the selected pump radiation source from feeding back into the selected at least one pump radiation source.

Abstract: An ultrafast digital optical signal processor includes a body of a third order nonlinear material and three input beams, two beams counterproprogating in the material on-axis and the third beam propagating off-axis, all simultaneously, to generate an output beam that counterpropogates with respect to the off-axis input beams. A set of three voltage controlled spatial light modulators are used for encoding the three input beams in accordance with a three-set Venn diagram based encoding scheme. The output beam is split into two parts which are decoded separately using a mask for one beam part and a spatial light modulator for the other beam part.

Abstract: A method and apparatus for generating a light pulse having a duration as short as about 3 picoseconds is disclosed. A 5 mJ 25 picosecond second harmonic light pulse from a Nd:YAG laser system is focused into a 5 cm cell filled with D.sub.2 O so as to generate a continuum light pulse spanning about 150 nanometers with an average energy of at least 20 nd/nm across the spectrum. The continuum light pulse is fed through a 10 nanometer narrowband filter centered at 580 nanometers, producing an output pulse having a duration of about 3 picoseconds. The pulse so produced has a number of uses including as a seed pulse for dye laser oscillators and solid state amplifiers or as a pump source for pumping ultrashort dye lasers.