As40S59Se1/As2S3 step index fiber for 1–5 μm supercontinuum generation

• The core/cladding preform was extruded by the isolated stacked extrusion method.
• As2S3 fiber with low loss (1 dB/m) and large core/cladding ratio (1:17) was drawn.
• Supercontinuum spectra covered the second atmospheric window were generated.

A high-purity As40S59Se1/As2S3 core/cladding step-index fiber for supercontinuum generation was fabricated in this study. The glass rods were obtained by using a relatively effective and inexpensive method of modified physical and chemical purification. Then, the multi-material fiber preform was fabricated through a modified laboratory using one-step co-extrusion process. Moreover, the fiber preform with a Polyether Sulfone (PES) polymer was drawn with a core diameter of ~ 22 μm. The core/cladding ratio of the fiber was approximately 1:17, and the minimum loss was approximately 1 dB/m between 4 and 6 μm. By pumping a 13 cm-long fiber with different laser powers and another two different lengths (20 cm and 50 cm, respectively) of fiber at 4.8 μm, a supercontinuum covering 1–5 μm could be recorded in all fibers. This study attained a 1–5 μm supercontinuum that covered the second atmospheric window. Result of this study can be a promising reference in the production of mid-infrared light source.