Accession Number : AD0465062

Title :   NEAR INFRARED ABSORPTION BAND IN CADMIUM SULFIDE SINGLE CRYSTALS,

Corporate Author : NAVAL RADIOLOGICAL DEFENSE LAB SAN FRANCISCO CA

Personal Author(s) : Alvares, Norman J.

Report Date : 26 APR 1965

Pagination or Media Count : 26

Abstract : Measurements of the absorption spectra of cadmium sulfide single crystals were made in the region of 0.5 to 15 microns and between the temperatures of 90 and 293 K. An absorption peak observed at 3.1 microns is apparently generated by a process of thermal stimulation. It appeared after the crystal was heated from 90 to 140 K or stored for long periods of time at 90 K. The 3.1 micron absorption peak is an indication of a trapping site with an energy of 0.4 ev. In order to verify this observation, a thermally stimulated current measurement was made with a CdS single crystal. The result of this measurement was that the location of the current peak essentially confirmed the optically observed trapping energy of 0.4 ev. The time response of gamma-induced current for the crystals in a flux of 10 r/hr were measured, and an attempt was made to correlate the time response measurements to the magnitude of the optical absorption peak; however, due to anomalies in the time response measurements, no definite comparisons could be made between these two parameters. The optical observations were able only to detect the presence of the absorption band, and not its energy location within the band structure of the crystal. (Author)

Descriptors :   (*ABSORPTION SPECTRA, CADMIUM COMPOUNDS), (*INFRARED SPECTRA, SULFIDES), (*SINGLE CRYSTALS, INFRARED SPECTRA), PHOTOCONDUCTIVITY, BAND SPECTRA, CRYOGENICS, GAMMA RAYS.

Distribution Statement : APPROVED FOR PUBLIC RELEASE