Exploring the Potential of Fluoride Optical Fibers for Sensing in the Mid-Infrared

All-fiber Mach-Zehnder interferometers have emerged as versatile solutions for sensing a number of parameters, including temperature, strain, and surrounding refractive index. Their operation relies on the interference between core and cladding modes, which generates a distinctive comb-shaped output spectrum that shifts in wavelength as a function of the monitored parameter changes [1]. Typically, single-mode fibers are employed, with cladding modes excited through non-adiabatic taper, S-taper, or off-axis splices.