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

• Arsenic-free low-loss fiber was fabricated by a process of peeled-off extrusion. • The fiber exhibits a minimum optical loss of 0.87 dB/m at 5.1 μm. • The broadest spectrum from 1.56 to 7.59 μm at −30 dB was achieved successfully. A low-loss and Arsenic-free sulfur-based chalcogenide fiber(Ge-Sb-S) was fabricated by a novel process of peeled-off extrusion. The fiber has an optical loss of <2 dB/m in a range from 5 to 6 μm with a minimum loss of 0.87 dB/m at 5.1 μm. A mid-infrared (MIR) supercontinuum (SC) spectrum covering 1.56–7.59 μm was generated from a 22-cm long fiber pumped with a femtosecond laser at 4 μm (−150 fs, 1 kHz). Simultaneously, we demonstrated that the optical fiber has a transmission efficiency of 53% at 4 μm, which is the key significance for applications such as IR night vision, bio-photonics, military defense and environmentally friendly industry. [ABSTRACT FROM AUTHOR]