Investigation of thermally stimulated luminescence and its description by a tunneling model

Abstract

Using a tunneling pair recombination model with the assumption of spatially distributed "ionized" pairs of luminescent centers and traps, a general and analytical expression of thermally stimulated luminescence (TSL) intensity is derived. The Hoogenstraaten and Bube methods of determining the activation energy are still valid in the tunneling model, except they determine the activation energy of the trap tunneling state. Based on explicit expressions for TSL, it is shown that the study of TSL shape yields information on the dependence of the pair distribution on phosphor excitation conditions. Experimental results on Zn2SiO4:Mn single crystals with or without arsenic codoping are presented.