Refractive index dispersion in ternary germanate glasses

• Published in: Japanese Journal of Applied Physics 1995, Vol.34 (10), p.5615-5620
• Main Authors: SAKAGUCHI, S, TODOROKI, S, RIGOUT, N
• Format: Article
• Language: English
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Exact sciences and technology; Optical constants (including refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity); Optical constants: refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Optical properties of bulk materials and thin films; Physics
• ISSN: 0021-4922; 1347-4065
• DOI: 10.1143/jjap.34.5615

The refractive index dispersion in germanate oxyfluoride glasses of GeO 2 -P 2 O 5 -MF 2 (M=Ca, Zn), which are developed for optical fiber application, is investigated in the 0.4-4 µ m wavelength range by the minimum deviation method. The prepared glasses have a GeO 2 content varying from 80 to 30 mol%. The dispersion curves for these glasses tend to shift to shorter wavelengths as the GeO 2 content is decreased. Material dispersions are also derived from the refractive index measurements and the zero-material dispersion wavelengths (λ 0 ) are found in the vicinity of 1.5 µ m. On the basis of the empirical relationship between λ 0 and the minimum loss wavelength (λ 0 ), the λ min values are located at around 1.8 µ m. A minimum loss of as low as 0.08 dB/km is expected for the present germanate glasses.