Synchrotron-Excited Luminescence of Natural Zircon

Abstract

The luminescence properties of two single zircon crystals from kimberlite of Yakutia have been studied, excited by the DORIS HASYLAB synchrotron, Germany, within energy range from the visible to the soft X-ray region (5-25, 50-200, and 500-620 eV) at temperatures of 300 and 10 K. The luminescence spectra in the range of 2.5 to 6.0 eV and excitation spectra of the main bands have been examined, the physical nature of the luminescence centers has been discussed, and the luminescence properties of a crystal containing growth (radiation) structural defects and a crystal with the same impurities but annealed in air at 1200°C are compared. The zoned structure of the mineral has been considered and the value of the energy gap (Eg) in the mineral has been estimated at 7.1 eV. Two groups of luminescence bands caused by impurities of intrinsic (growth, radiation) nature (Emax = 2.1, 2.7-2.8, and 3.2-3.3 eV) and matrix luminescence (Emax = 4.4-4.7 and 5.4 eV) probably with the participation of excitons were distinguished on the basis of selective excitation of zircon with different synchrotron energies relative to the gap value (Eexcit <Eg, Eexcit ~ Eg, and Eexcit > Eg). The short-lived component with a response time of 4 ns has been revealed in the afterglow of zircon in the region of 5.4 eV. © 2010 Pleiades Publishing, Ltd.