A Study of the Mechanics of Radiation Damage in Fiber Optical Waveguides.
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)
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 1984
- Accession Number
- ADA139590
Entities
People
- G. R. Blair
Organizations
- HRL Laboratories