Patterns of glow peak movement in rare earth doped lanthanum fluoride

Low temperature thermoluminescence data from rare earth doped lanthanum flu oride is characterized by numerous glow peaks. These differ in temperature as a function of the substituted rare earth ion, dopant concentration and t hermal annealing. Analysis of the component bands in terms of activation en ergy, frequency factor and kinetic order reveals simple patterns in which t he movement of the glow peaks is related to the ionic radii of the rare ear th ions. Models for the thermoluminescence signals resulting from close: as sociation of the dopant recombination sites and the charge traps are discus sed. Further consideration of a preference for impurity clustering, in orde r to reduce lattice strain, is used to explain the concentration and anneal ing induced changes. (C) 2000 American Institute of Physics. [S0021-8979(00 )03717-8].