Extending the dose range: Probing deep traps in quartz with 3.06 eV photons

Abstract

This article demonstrates that violet (405 nm) stimulated luminescence (VSL) signal from quartz contains contribution from deep traps that are otherwise not accessible with blue light (470 nm). Additionally, it also contains the typical fast and slow components observed with the blue light stimulation. Although, the fast OSL component is measured with similar efficiency by blue and violet lights, the slower OSL components (especially S 3) are measured relatively more efficiently with the latter. New insight into the origins of quartz luminescence is presented through a comparison of violet and blue lights stimulation, and thermal stimulations. Finally, it is shown that the deep traps probed through violet light stimulation have potential for increasing the dose measurement/dating range using quartz. The post-blue VSL signal allows easy, precise measurement of dose up to at least 1 kGy in our samples, while the initial BSL signal shows saturation at ∼100 Gy. The violet stimulation provides a means for optically probing the traps that give rise to signals with extended growth (dose-response) characteristics such as high temperature isothermal TL (ITL), the slow component OSL, and perhaps also the thermally transferred-OSL (TT-OSL).