Characteristics of time-resolved luminescence in quartz

Time-resolved luminescence measurements were performed with samples of synthetic quartz (Sawyer Premium Q) and granular quartz extracted from ceramics and sediment samples under pulsed (similar to5 ns) laser stimulation (OPO). The luminescence was detected in the UV region using colour glass filters (FWHM 280-380 nm). The time-resolved spectrum is dominated by a single exponential decay that remains substantially unaltered when the stimulation wavelength is changed from 600 to 450 nm indicating that the same recombination process is being observed. The lifetime measured at room temperature was 40+/-0.6 mus for the synthetic quartz; at elevated temperatures the measured lifetime is reduced in a manner that is consistent with a competitive non-radiative recombination process (thermal quenching). An average lifetime of 33+/-0.3 mus was obtained for seven samples of granular quartz, indicating a common recombination process in these natural samples that differs from the value for synthetic quartz. (C) 2000 Published by Elsevier Science Ltd. All rights reserved.