Arsenic-free low-loss sulfide glass fiber for mid-infrared supercontinuum generation

A low-loss and Arsenic-free sulfur-based chalcogenide fiber(Ge-Sb-S) was fabricated by a novel process of peeledoff extrusion. The fiber has an optical loss of <2 dB/m in a range from 5 to 6 mu m with a minimum loss of 0.87 dB/m at 5.1 mu m. A mid-infrared (MIR) supercontinuum (SC) spectrum covering 1.56-7.59 mu m was generated from a 22-cm long fiber pumped with a femtosecond laser at 4 mu m (-150 fs, 1 kHz). Simultaneously, we demonstrated that the optical fiber has a transmission efficiency of 53% at 4 mu m, which is the key significance for applications such as IR night vision, bio-photonics, military defense and environmentally friendly industry.