Optical absorption and thermoluminescence of KCl single crystals coloured under DC fields

The optical absorption and thermoluminescence of KCl single crystals X‐irradiated at 300 and 373 K are studied in presence of large de fields (0 to 22 kV/cm). With de field the F band peak shifts to the higher frequency side and the overall colour centre concentration is observed to increase. The shift in F band is attributed to a shrinkage in the lattice parameter (at the dislocation region) due to the mobile anion impurity experiencing the applied field. The preferential movements of charges may decrease the rate of recombination of the generated carriers resulting in an increase in colour centre concentration. An attempt is made to analyse these data. Copyright © 1983 WILEY‐VCH Verlag GmbH & Co. KGaA