ODMR OF CD IMPURITY CENTERS IN GG IRRADIATED BAF2 CRYSTALS

The magnetic circular dichroism of the optical absorption (MCD), optic ally detected magnetic resonance (ODMR) as well as ESR and luminescenc e in Cd- doped BaF2 crystals gamma-irradiated at RT were investigated. MCD signals centered at 295 nm, 290 nm and 365 nm are observed, toget her with corresponding radiation induced optical absorption bands in t he same wavelength regions. The ODMR detected in all these bands is ca used by hyperfine (hf) interaction of unpaired spin with Cd- nucleus. Three types of different Cd- related defects have been separated: 1) C d-c(+) represented by the MCD of derivative type centered at 295 nm an d hf constant A(Cd) = 480 mT, 2) Cd-c(+)-center having lowered symmetr y of the nearest neighbours and represented by derivative- type MCD ce ntered at 290 nm and A(Cd) = 370 mT. The nature of perturbation is not clear yet. The ESR spectrum of perturbed Cd-c(+)-center significantly differs from that of the regular Cd-c(+)-center. 3) Center represente d by the MCD around 365 nm and the hf constant A(Cd) = 380 mT which is attributed to Cd+(1)-type center.