Slow components of the emission decay in fluoride crystals doped with Ce3+

Abstract

Spatially separated defects created by photons with energies 6–8 eV in alkali-earth fluoride crystals doped with cerium are investigated with the help of thermoluminescence. Measuring the spectra of creation of Vk and H peaks of thermostimulated luminescence inBaF2:Ce3+. we demonstrate that photons with energies higher than 6eV induce H centers (self-trapped holes captured by interstitialF ions), whereas the formation of self-trapped holes begins on exposure to photons with energies greater than 7 eV. The influence of photoionization on theCe3+ luminescence inBaF2, SrF2, CaF2, andCeF3 crystals is investigated in the range of photon energies 4–8 eV. An exponentialCe3+-emisson decay was observed for excitation energy lying in the range 4–6 eV. Slow and fast decay components were observed under excitation by photons with energies higher than 6 eV. We believe that the slow and fast components are due to the tunnel recombination of trapped electrons with hole centers.