Showing papers by "Philip St. J. Russell published in 1990"
TL;DR: Photoinduced guided index changes approaching 10−4 in the range 488–784 nm, measured using a simple interferometric technique, are reported in germanosilicate single-mode optical fibers exposed to the 488-nm line of an Ar+ laser running multifrequency.
Abstract: Photoinduced guided index changes approaching 10−4 in the range 488–784 nm, measured using a simple interferometric technique, are reported in germanosilicate single-mode optical fibers exposed to the 488-nm line of an Ar+ laser running multifrequency. The wavelength dependence and dynamics of the writing process are characterized, and the material dispersion of the induced Δn(λ) is shown to be weak. The effect is placed in the context of related research on color centers in these fibers, and two different mechanisms are proposed that lead to quantitative estimates in rough agreement with the measured Δn values.
275 citations
Patent•
31 Jan 1990
TL;DR: In this paper, an optical fiber is electrically poled by applying an intense external electric field across the fibre core and sustaining this field for a prolonged period of time, and permanent linear electro-optic property is imparted to the fibre.
Abstract: An optical fibre is electrically poled by applying an intense external electric field across the fibre core and sustaining this field for a prolonged period of time. In this manner, a permanent linear electro-optic property is imparted to the fibre. Poling may be accelerated by performing this method at elevated temperature. Highest field intensities can be achieved using a fibre having one or two internal electrodes i.e. electrodes incorporated in the fibre cladding. Preferably the internal electrodes are of a metal or metal alloy that is liquid at poling temperature.
19 citations