Chalcogenide glass fibers with a rectangular core for polarized mid-infrared supercontinuum generation.

A step-index chalcogenide fiber with a rectangular core and a circular cladding was fabricated through an approach that combines an extrusion technique and a multiple-stage rod-in-tube method. This fiber has a Ge 12 As 24 Se 64 glass core with a size of ~2.8 μm × 5.9 μm, and a Ge 10 As 24 S 66 glass cladding with a diameter of ~220 μm, and shows a relatively large birefringence. When ~10 cm long fiber was pumped at 4.0 μm with 330 fs pulses, ~2.2–9.5 μm supercontinuum with a flatness of 20 dB and a polarization extinction ratio of ~10 dB was generated. • A chalcogenide glass fiber with a rectangular core is designed. • The fiber is fabricated by an extrusion technique and a rod-in-tube method. • The fiber shows a background loss of about 3.1 dB/m in the mid-infrared. • Polarized ~2.2–9.5 μm supercontinuum is generated in the fiber. [ABSTRACT FROM AUTHOR]