Accession Number : ADA139590

Title :   A Study of the Mechanics of Radiation Damage in Fiber Optical Waveguides.

Descriptive Note : Final rept. Sep 80-Dec 83,

Corporate Author : HUGHES RESEARCH LABS MALIBU CA

Personal Author(s) : Blair,G R

PDF Url : ADA139590

Report Date : Mar 1984

Pagination or Media Count : 30

Abstract : Ionizing radiation on optical fibers induces large transmission losses. The permanence and intensity of the damage depends on the concentration of germanium and phosphorus. The sensitive structure(s) may act as electron or hole traps when illuminated with gamma rays (1.2 meV) or ultraviolet (4.9 eV). The process of emptying traps by heat and refilling with UV (254 nm) can be done repeatedly. These traps re-populated by UV are the same as the transmission loss traps due to gammas. Certain TL traps cannot be re-populated with UV. The nonrefillable TL traps exist in those glasses which have the GeO2/P2O5 ratios smaller than 4. Higher ratio glasses exhibit one refillable peak which bears an inverse relationship to germanium content. The TL traps have a depth of about 0.85 eV. Pure silica fibers display a permanent thermoluminescence. The presence of these traps is not detected by transmission measurements. Based on UV thermoluminescence, transmission, and UV fluorescence measurements, it is suggested that Ge(+2) plays an important role in the damage mechanism. (Author)

Descriptors :   *Optical waveguides, *Fiber optics, *Radiation damage, Ionizing radiation, Transmission loss, Thermoluminescence, Holes(Electron deficiencies), Trapping(Charged particles), Ultraviolet radiation, Filling, Glass fibers, Germanium, Phosphorus, Silicon dioxide, Fluorescence, Measurement, Light transmission, Signals, Absorption, Defects(Materials), Radiation dosage, Irradiation, Gamma rays

Subject Categories : Radioactiv, Radioactive Wastes & Fission Prod
      Fiber Optics and Integrated Optics

Distribution Statement : APPROVED FOR PUBLIC RELEASE