Antiresonant reflecting microstructured optical fibers for the mid-infrared

We report on the demonstration of silver halide (AgCl_xBr _1-x) microstructured optical fibers (MOFs) based on the antiresonant reflecting optical waveguide (ARROW) model, for the mid-infrared. MOFs with low index core surrounded by an octagonal structure of high index rods were designed and fabricated. The fibers exhibited transmission spectra with narrow stopband frequencies in the 9-11 μm range. The location of the transmission minima matched the theoretical predictions by the ARROW model. The measured propagation losses in the maximum transmission range were ∼60 dB/m. Imaging the output of the MOFs at the passband wavelengths revealed single mode guidance in the core.