High-coupling efficiency and robust fusion splicing between fluorotellurite and chalcogenide fibers

• This is the first time to achieve a high-quality and robust fusion splicing between fluorotellurite and As 2 S 3 fibers. • The loss of fusion splicing between silica and fluorotellurite fibers is 0.5 dB, the fusion-splicing point between fluorotellurite and As 2 S 3 fibers is achieved with a splicing loss of approximately 0.55 dB. This work lays a solid foundation for building an actual all-fiber cascaded mid-infrared supercontinuum source. • The beam quality can be well maintained through the fusion splicing point between fluorotellurite and As 2 S 3 fibers. Besides, the temperature of the splicing joint has no evident increase with a 2 W pump power at 1.55 μm. We demonstrate a low-loss and high-robustness fusion splicing point between fluorotellurite fiber and arsenic sulfide-based chalcogenide fiber (As 2 S 3 ) by using an asymmetric fiber splicing technology. The splicing loss of point is less than 0.55 dB at the wavelength of 1.55 μm, and the monitored tension is 129 g by tuning the distance of the fusion splicing head offset in the fusion splicing process. Using an all-fiber testing system, the fusion splicing point loss between the 1.55 μm testing light source tail fiber (silica fiber) and the fluorotellurite fiber is 0.503 dB. The output power from the As 2 S 3 fiber is 0.91 W with a testing light source of 2 W, and the temperature of the splicing joint shows no evident increase. This finding indicates that the fusion splicing point offers excellent beam quality. This work lays a solid foundation for building an all-fiber cascaded system generating mid-infrared supercontinuum with high-coupling efficiency between mid-infrared soft-glass fibers.