Abstract

Color center formation and luminescence excitation in BaFBr single crystals by X-ray irradiation was studied at low temperatures. F(Br−) centers formed by X-irradiation at LHeT showed an absorption band at 2.09 eV at LHeT. This peak energy is different from those of isolated F(Br−) centers, suggesting formation of F centers perturbed by nearby impurities or defects. A dichroic absorption band due to self-trapped holes, VK(Br2−) centers, was observed at 3.35 eV. The dichroism of the VK(Br2−) band diminished above 110 K. Three luminescence bands were observed at 5.2, 3.9, and 2.5 eV when BaFBr single crystals were X-irradiated at LHeT. Among these luminescence bands, the 5.2 eV band can be attributed to the recombination of VK centers with electrons.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call