Effect of Temperature on Processes of Radiation-Induced Generation of Primary Defects in MgF_2 Crystals

摘要

The spectral and kinetic parameters of the absorption and emission relaxation initiated by a single nanosecond-range electron pulse in MgF_2 crystals are studied in the temperature range 20-550 K. It is found that the relationship between the two channels of dissipation of the electronic excitation energy (generation of F centers and short-lived excitons) does not depend on the temperature of the irradiated crystal in the temperature range 20-120 K and changes in favor of the F centers at T ≥ 150 K. The temperature quenching of the 3.2-eV exciton emission at T ≥ 60 K is detected. The ionic structure of the short-lived excitonic state is discussed.