Accession Number : AD0621488

Title :   LASER MATERIAL (SPECTROSCOPY).

Descriptive Note : Semiannual rept. no. 1, 15 Dec 64-15 Jun 65.

Corporate Author : STANFORD UNIV CALIF MICROWAVE LAB

Report Date : JUL 1965

Pagination or Media Count : 135

Abstract : The line structure of the photoluminescence of ZnS:Tb, ZnS:Nd, ZnS:Tm and ZnS:Dy has been studied under various preparative conditions. There is a strong tendency for rare earth pairing with other lattice defects in the presence of excess S. This pairing is manifested by the appearance of new emission and excitation bands. Of the many distinct sites for the rare earth ion, one seems to stand out as most important in electroluminescence although it gives only a minor contribution to the photoluminescence. Using a variety of luminescent phenomena, we are able to count at least four distinct sites for trivalent rare earth ions in ZnS and there is strong evidence that more exist. Preparation of CdS:Nd has been achieved so that reasonably strong Nd(3+) emission is obtained. A multiplicity of Nd(3+) sites is evident. Emission of CdS:Er has also been observed. Tunnel injecting contacts have been formed on slices of a single crystal of CdS:Nd. The belowthreshold oscillation spectral width is derived. The above-threshold spectral width due to phase fluctuations in the oscillator output is given. The above-threshold spectral width due to amplitude fluctuations (the AM contribution to the spectral width) is given. A practical Nd:YAG CW laser system has been designed and built. An aluminized glass, cylincrical cavity was used, and a linear tungsten filament, ASA-DXN 1000 watt lamp was used as an optical pump. The laser threshold was between 900 and 1000 watts. (Author)

Descriptors :   (*SEMICONDUCTORS, LASERS), (*LASERS, MATERIALS), ZINC COMPOUNDS, SULFIDES, IMPURITIES, RARE EARTH ELEMENTS, TERBIUM, NEODYMIUM, THULIUM, DYSPROSIUM, ERBIUM, YTTRIUM, ARGON, GARNET, LUMINESCENCE, ELECTROLUMINESCENCE, SINGLE CRYSTALS, PUMPING(ELECTRONICS), ULTRAVIOLET SPECTRA, VISIBLE SPECTRA, OSCILLATORS

Distribution Statement : APPROVED FOR PUBLIC RELEASE