Material dispersion and Rayleigh scattering in glassy germanium dioxide, a substance with promising applications in low-loss optical fiber waveguides

Abstract

An investigation was made of the dispersion of the refractive index n (λ) of glassy GeO2 in the spectral range 0.5–2.5 μ. It was found that this dispersion of GeO2 vanished near λ0 = 1.74 μ. The Brillouin scattering method was used to determine the elastic and photoelastic constants of GeO2 and to find the Rayleigh scattering coefficient, which indicated that the upper limit for the Rayleigh scattering losses was 0.30 dBAm at the wavelength of μ = 1.74 μ. The possibility of using GeO2 fibers is considered and their advantages over SiO2 fibers in the wavelength range 1.7–1.8 μ are stressed.