S.S.Novosad
Received June 30, 1998, in final form July 12, 1999
Optical absorption spectra, spectral sensibility of the photoelectret
state and luminescence properties of the cadmium bromide crystal activated
from the melt by metallic cadmium have been investigated under both
X-ray and N2-laser excitation. Basing on the CdBr2,
CdI2>, CdBr2:CdI2, CdBr2:CdO and
CdI2:Cd spectral characteristics, it has been found that
a super-stoichiometric cadmium presence in CdBr2 causes an
increase of the self-activator center concentration responsible for
the luminescence with maximum at 640-650 nm. This emission has
been assumed to be caused by anion excitons localized on bromine vacancies,
which form associates with interstitial cadmium atoms. The thermal
activation energies of trapping centers responsible for the thermostimulated
luminescence of CdBr2:Cd in the 85-295 K temperature
interval have been estimated. The nature of trapping levels in cadmium
bromide crystals is discussed.