A scalable and accurate technique for measuring the group index and dispersion of optical fibers is used to provide the first accurate measurements of dispersion slope in hollow-core photonic band-gap fibers. We present data showing group index, group-velocity dispersion and dispersion slope in hollow-core fibers guiding at both 800 nm and 1064 nm wavelength.
Welch, M. G., De Nobriga, C. E., Correa, R. A., Wadsworth, W. J., & Knight, J. C. (2009). Accurate measurement of the dispersion of hollow-core fibers using a scalable technique. Optics Express, 17(11), 9006-9012. https://doi.org/10.1364/OE.17.009006