Critically Evaluated Data on Optical and Transport Properties of Solids (Refractive Index and Absorption Coefficient of Selected Optical Materials)
Abstract
In this report, experimental material on the absorption coefficients of alkaline earth halides was searched, compiled, and analyzed. It was found that the bulk of available data was concentrated to the absorption edges of the main transparent region for the four materials calcium fluoride, strontium fluoride, barium fluoride, and magnesium fluoride. An equation was formulated to best describe the absorption data in the infrared multiphonon region as a function of both frequency and temperature. It was noted that the same type of equation is equally valid for both alkaline earth halides and alkali halides. Although the intrinsic abosrption was predicted by the proposed equation, discrepancies might occur in the region where absorption is extremely low and where extrinsic absorptions due to impurities and surface contamination dominate the intrinsic absorption by factors ranging from fractions to multiples of ten. Experience has shown that extrinsic contributions can be reduced through improved crystal growing and surface polishing techniques. The work on the absorption coefficient of silicon and germanium was in progress. It was found that the absorption coefficient is sensitive to the amount and kind of impurities usually being introduced as desirable dopants. Numerous experimental material was made available. Currently the work remained in the stage of data extraction and compilation.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 03, 1980
- Accession Number
- ADA086658
Entities
People
- H. H. Li