Effects of doping, Gamma irradiation, and annealing on the temperature dependence of the photocurrent through bismuth titanate crystals

摘要

The separate and combined effects of doping, annealing, and gamma irradiation on the temperature- dependent photocurrent through nominally undoped and doped sillenite-type crystals were investigated between 77 and 300 K. The results were interpreted using a band-structure model describing the recombination processes involved in terms of deep slow and fast recombination centers(r-and s-centers)and shallow traps. The electron transition to recombination centers were shown to be controlled by the trap level E_t. The thermal Stability of radiation-induced defects was assessed.