Recent advances in ultra-wideband Raman amplifiers

This talk will review fundamentals of ultra-wideband Raman amplifiers, recent progress of high power pump lasers, and system applications of Raman amplifiers. Pump wavelength determines the gain spectrum of a Raman amplifier. This implies that the gain created by a multi wavelength pumping can have a wideband gain profile, which is approximately described by a linear superposition of each gain by individual pumping, Therefore, in order to realize wideband Raman amplifiers, pump lasers with optimally different wavelengths have to be multiplexed efficiently.