Rayleigh scattering in K2O-MgO-SiO2 and Na2O-B2O3-SiO2 glasses

We investigated the Rayleigh scattering of ternary glass systems K2O-MgO-Si O2 and Na2O-B2O3-SiO2. The minimum Rayleigh scattering coefficients in both glasses were considerably lower than that in pure silica glass. The Raylei gh scattering due to concentration fluctuation of Na2O-B2O3-SiO2 glass incr eased rapidly with decreasing Na2O content. By contrast, that of K2O-MgO-Si O, glass was almost independent of the K2O content. We found that K2O-MgO-S iO2 glasses with a high SiO2 content (70 similar to 75 mol%) can be expecte d as candidates for fabricating ultralow loss fiber because of their low Ra yleigh scattering, zero material dispersion wavelength near 1.55 mu m. (C) 2000 Academic Press.