Dynamic line-by-line pulse shaping with GHz update rate

Abstract
We introduce a novel scheme for dynamic line-by-line pulse shaping with GHz update rates. Four lines of an optical frequency comb source are used to injection-lock four individual VCSEL, which are subsequently electrically modulated at 0.4 to 1GHz through current modulation. This concept could be considered a completely new way of pulse shaping as the light is not simply modified, but rather regenerated with the desired properties. We also discuss an important drawback of line-by-line pulse shapers that ultimately limits the modulation speed capability.