Abstract

In an effort to explain anomalous thermoluminescence (TL) measurements, that cannot be described by the well-known 1st and 2nd order kinetics, more general TL kinetics have been developed. The anomalous results include glow peak shapes that cannot be described by the usual kinetics, the appearance of physically unrealistic parameters that are unusual functions of the premeasurement dose, etc. As is well known, the usual 1st order TL kinetics is obtained from an expression, called here the general one-trap kinetic equation, by assuming that thermally released trapped charges undergo light emitting recombination without being retrapped. The usual 2nd order kinetics is obtained, from the same equation, by assuming that retrapping occurs and, first, that the retrapping and recombination cross sections are equal, and, second, the trapped electron and hole concentrations are equal. The general one-trap kinetic equation has been investigated by numerically computing glow curves using physically reasonable parameters. In turn, these curves are regarded as "data" and analyzed by fitting them to the usual 1st and 2nd order expressions. A number of anomalous results are reproduced. The computed glow peaks depend strongly on the dose, the retrapping-recombination cross section ratio, etc. They are approximated, but not in the wings, by the usual 1st and 2nd order kinetics. However the kinetic parameters obtained usually differ appreciably from those used to compute the glow peaks.

© 1984 Optical Society of America