Extending the transmission of a silica hollow core fiber to 4.6 mu m

In this work, an anti-resonant hollow core fiber was designed for 3-5 pm transmission and fabricated from fused silica. Due to strong core confinement, low transmission loss was measured in the MWIR, with only 0.128 dB/m loss at 4.05 pm and 0.316 dB/m loss at 4.63 pm. This pushes the usable transmission windows and the potential application areas for silica-based ARHCF beyond what has previously been shown to be possible.