We propose new transition metal (TM)-doped ZnSe=As2S 3:As2Se3 composite materials for mid-IR fiber lasers. The composites are the suspension of crystalline micro- and nanosized TM2+:ZnSe or TM2+:ZnS powders in chalcogenide glasses with the refraction index matching. Mid-IR room-temperature lasing of Cr 2+:ZnSe=As2S3:As2Se3 microcomposite material is demonstrated at the 2:4 μm wavelength. © 2011 Optical Society of America.
