Time-division multiplexing of pump wavelengths to achieve ultrabroadband, flat, backward-pumped Raman gain.

Abstract
We describe a simple scheme, which we call the Raman smart pump, to allow for the achievement of flat gain over broad bands with backward-pumped Raman amplification. The proposed method, based on time-division multiplexing, also removes all interaction among the various pump wavelengths and allows for dynamic gain control through simple electronic means.