Multiple-order stokes pulse generation by nitrogen-laser-pumped fiber Raman laser

A multimode silica-core fiber Raman laser was pumped by a compact Blumlein-type nitrogen laser. Four orders of Stokes pulses were obtained in the range of 341-359 nm at 280 MW/cm
²
fiber input. All the Stokes pulses were expanded by modal dispersion. The threshold of each Stokes pulse was measured and the energy transfer to the next order was observed. Conditions for efficient conversion to the required-order Stokes pulse are discussed.