Showing papers by "E. J. Friebele published in 1978"
TL;DR: In this article, the radiation-induced optical attenuation has been measured over a wide range of dose and time in state-of-the-art step-and graded-state 60Co and pulsed electron irradiation.
Abstract: The radiation‐induced optical attenuation has been measured over a wide range of dose and time in state‐of‐the‐art step‐ and graded‐state 60Co and pulsed electron irradiation. Results are reported for previously uncharacterized silica fibers containing dopants such as Ge,P,B,F,Tl, and Cs. At short times following the irradiation, fibers which contain Ge exhibit an extremely high attenuation that is not observed when these fibers contain P. Recovery is typically more complete in the silica core fibers than in the doped silica core fibers, which can have losses 25–1000 times the intrinsic loss 3 months after an irradiation of 105–106 rad.
38 citations
TL;DR: In this article, the results of the recent models of charged defects in chalcogenides were discussed in terms of the effect of the charged defects on the photoluminescence and photoinduced ESR.
Abstract: Thallium in $a$-${\mathrm{As}}_{2}$${\mathrm{Se}}_{3}$ reduces transient hole transport but has no effect upon the photoluminescence and photoinduced ESR. The results are discussed in terms of the recent models of charged defects in chalcogenides.
38 citations
TL;DR: In this article, a density of paramagnetic states which increases with temperature has been observed and characterized in amorphous As using ESR and optical absorption techniques, which are interpreted as thermal excitation of strained bonds at As vacancies.
33 citations
TL;DR: In this article, the optical attenuation induced in polymer-clad silica fiber-optic waveguides by low-dose ionizing radiation (0.5-14 MeV) has been found to be much greater than expected on the basis of previous high-dose measurements.
Abstract: The optical attenuation induced in polymer‐clad silica fiber‐optic waveguides by low‐dose ionizing radiation (0.5–14 MeV) has been found to be much greater than expected on the basis of previous high‐dose measurements. The radiation sensitivity is dependent upon the purity and OH content of the silica and upon the radiation history of the fibers, but it does not appear to depend upon the drawing conditions nor on the limited radiation‐induced loss in the polymer cladding. The damage is greater at short times following the irradiation, and the decay kinetics of different synthetic silica fibers are qualitatively the same.
32 citations
TL;DR: In this paper, the response of fiber optic waveguides to ionizing radiation has been studied and it was shown that fibers with low OH are more susceptible to damage than those with high OH.
Abstract: The response of fiber optic waveguides to ionizing radiation has been studied. Measurements of the growth and decay of the radiation-induced loss at 0.82μ have revealed that fibers with low OH are more susceptible to damage than those with high OH. The addition of P to Ge-doped silica core fibers has been found to suppress an intense transient absorption. Spectral measurements of the radiation-induced absorption between 0.4 - 1.7μ have shown an increase in the OH overtone and combination band intensity with irradiation so that the induced loss at 1.3μ is actually less in the low OH content silica core fibers than in the high OH content fibers. Real time spectral measurements of the damage following a pulsed irradiation have lead to an identification of the absorption bands and damage mechanisms responsible for the radiation-induced absorption.
26 citations