Tubular anti-resonant hollow core fiber for visible Raman spectroscopy

We report low loss, wide bandwidth, tubular anti-resonant hollow core fibers with a low macro- and micro- bend sensitivity tailored for gas sensing using visible wavelength Raman spectroscopy. The fibers show record low bend sensitivity for anti-resonant fibers operating in this spectral region. A minimum loss of 23.6 dB/km is measured at 570nm for a fiber spooled on a 30cm diameter drum.