Article

Refractive index dispersion of doped silica for fiber optics

Optics Communications (Impact Factor: 1.44). 01/2002; 213:301-308. DOI: 10.1016/S0030-4018(02)02087-4

ABSTRACT The spectral dependencies of refractive index have been measured in Ge-, P-, N-, Cl-, B-, F-, and Al-doped silica glasses as well as in undoped silica glasses using bulk prism samples cut from optical fiber preforms. The latter have been fabricated by MCVD-, PCVD-, and SPCVD-processes. Based on the experimental results, material dispersion in the glasses has been analyzed, which is one of the most important parameters for fiber optics. An assumption has been made regarding the origin of the significant discrepancy of the zero-dispersion wavelength of nominally identical glass compositions in different publications. The effect of chlorine admixture on the dispersion curves has been investigated. Nitrogen-doped silica is shown to be a promising material for broadband graded-index multimode fibers.

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