SUBMILLIMETER ELECTRON-NUCLEAR EXCITATION-SPECTRA IN CSCDBR3-LN(3+) (LN=TM, HO) CRYSTALS

The ESR spectra of single and pair impurity centers of thulium and hol mium ions in CsCdBr3:Tm3+ and CsCdBr3:Ho3+ crystals are measured in th e frequency range 160-400 GHz. Analysis of the characteristic features of the hyperfine structure of the ESR lines and analysis of the varia tions in the spectra as a function of the temperature and external mag netic field shows that the Ln(3+) ions substitute for Cd2+ ions and pr edominantly form symmetric pair centers of the type Ln(3+)-(vacancy at a neighboring Cd2+ site)-Ln(3+). The ESR spectra of CsCdBr3:Ln(3+) cr ystals are used to make a positive identification of the optical spect ra of selective laser excitation. (C) 1997 American Institute of Physi cs.