Design of an efficient Mid-IR light source using As2S3 based highly   nonlinear microstructured optical fibers
  We report on the design of a highly-nonlinear specialty fiber as a mid-infrared light source at 4.3 {\mu}m. A meter length of the designed solid-core chalcogenide based index-guided microstructured optical fiber (MOF) with circular air holes has been exploited to translate wavelength via four wave mixing using a thulium-doped fiber laser as the pump with a relatively low peak power of 5 W. A peak gain value of around 37 dB with full width at half maxima (FWHM) less than 3 nm is achieved. 
A. Barh, S. Ghosh, G. P. Agrawal, R. K. Varshney, I. D. Aggarwal, and   B. P. Pal
physics.optics