Mid-infrared supercontinuum generation in low-loss single-mode Te-rich chalcogenide fiber

A single-mode Te-rich chalcogenide (ChG) fiber for mid-infrared has been fabricated via an isolated extrusion method. The optical loss of the fiber is 3-4 dB/m in a range of 6.5-10.5 mu m. Mid-infrared (MIR) supercontinuum (SC) generations were experimentally investigated in the step-index single-mode fiber with femtosecond laser pulse from an optical parametric amplifier (OPA). By pumping 17 cm-long fiber at 5 mu m and 8 mu m, the spectra spanning from 1.8 to 15 mu m and 2.3 to 14.5 mu m, respectively, were observed. The results show that the efficiency of SC generation is highest by pumping at near zero dispersion wavelength in single-mode fiber. It reveals that the superiority of single-mode fiber in SC generation over multimode is the elimination of high-order modes (HOMs) interaction. Besides, a repeat SC experiment was carried out for fiber stability test after half a year. (C) 2019 Optical Society of America under the terms of the OSA Open Access Publishing Agreement