NEAR INFRARED ABSORPTION BAND IN CADMIUM SULFIDE SINGLE CRYSTALS,

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)

Document Details

Document Type
Technical Report
Publication Date
Apr 26, 1965
Accession Number
AD0465062

Entities

People

  • Norman J. Alvares

Organizations

  • Naval Radiological Defense Laboratory

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Absorption
  • Absorption Spectra
  • Band Structures
  • Compound Semiconductors
  • Crystals
  • Energy Bands
  • Measurement
  • Observation
  • Optical Absorption
  • Single Crystals
  • Spectra

Fields of Study

  • Physics

Readers

  • Nuclear and Radiation Engineering.
  • Optical Physics and Photonics.
  • Plasma Physics.