Tunable Raman lasing in an As2S3 chalcogenide glass microsphere.

We demonstrate experimentally Raman lasing in an As2S3 chalcogenide glass microsphere pumped by a C-band narrow line laser. Single-mode Raman lasing tunable from 1.610 μm to 1.663 μm is attained when tuning a pump laser wavelength in the 1.522-1.574 μm range. When the pump power significantly exceeds the threshold, multimode cascade Raman lasing is achieved with the maximum Raman order of four at a wavelength of 2.01 μm. We also report an up-converted wave generation at 1.38 μm which is interpreted as the result of four-wave mixing between the pump wave and the wave generated in the second Raman order. The numerical results based on the simulation of the Lugiato-Lefever equation agree with the experimental results.