Indium Fluoride Optical Fiber End-Pump Combiner for High-Power All-Fiber Sources

In this paper, tapering and splicing techniques for optical fibers based on fluoride glass are illustrated, valuable for the next generation of all-fiber lasers emitting in the mid-infrared spectral range. In particular, a 5×1 optical fiber combiner is fabricated via stretching and heating technique. The performance of the device is assessed via superluminescent diode emitting around the wavelength $\lambda=1.55 \mu \mathrm{m}$. The splicing of two fluoride optical fibers is also investigated, due to the need to splice the output port of the 5×1 optical fiber combiner with a rare-earth doped optical fiber.