Simultaneous excitation of selective multiple Raman Stokes wavelengths (green-yellow-red) using shaped multi-step pulses from an all-fiber MOPA system

Abstract

We report the simultaneous excitation of multiple Raman Stokes lines in a 250 m long fiber using multi-step pump pulses. The frequency doubled output of a single polarization all-fiber Yb-doped MOPA operating at 1060 nm was used as the pump source. By adjusting the pump power and the pulse profiles we achieved the simultaneous excitation of green (1st Stokes), yellow (4th Stokes) and red light (6th Stokes) using 3-step pulses or the combination of any two using 2-step pulses. Through the use of pulse shaping we generate sequences of colored pulses with the flexibility of providing dynamic, agile frequency tuning between well-defined wavelengths.