Abstract

It is important to determine the dispersion of the Kerr effect in optical fibres for application to fibre communication and fibre sensors; little information on this effect presently exists in the literature. The Kerr coefficient K, has been found to vary with material, wavelength, and temperature. The classical Havelock's Law¹ has the form of K = c(n² - 1)²/E²nλ where λ is the wavelength, c is a material constant and independent of wavelength, n is the refractive index, and E is the applied electric field. Havelock's law appears adequate for some materials. It has been verified experimentally by several investigators.^2,3 In order to measure the very small Kerr coefficient for silica optical fibres, the experimental arrangement in Fig. 1 was used. The Kerr coefficient K = dI₀/IπlE² can be measured by detecting the parameters dI_0, the light intensity variation, I, the total light intensity, E, the applied electric field, and l, the length of the fibre.

© 1994 IEEE