Effect of the Gamma-Ray Irradiation on the Electric and Optical Properties of SrTiO₃ Single Crystals

We investigated the visible emission property of SrTiO₃ (STO) single crystals irradiated with gammy-ray (γ-ray) at various total doses up to 900 kGy. The electric and optical absorption properties of the irradiated STO samples were hardly changed with the γ-ray irradiation, compared with those of un-irradiated STO. In contrast, the visible emission near 550 nm increased with the γ-ray dose increasing. While the development of the visible emission was indicative of the increase of oxygen vacancies inside STO by the γ-ray irradiation, the newly generated oxygen vacancies were not significantly harmful to the electric and optical properties of STO. We concluded that the STO single crystal should have a good tolerance against the damage by the γ-ray irradiation.