Optical absorption of Yb-doped SrCeO₃ by electron irradiation

Radiation effects on the optical absorption of orthorhombic perovskite-type oxide (Yb-doped SrCeO₃) ceramics have been studied at room temperature using 1.8 MeV electrons at a dose rate of 300 Gy/s. The optical absorption in the wavelength range 460 to 800 nm is significantly reduced by annihilation of two absorption bands at approximately 585 and 695 nm as the electron irradiation dose increases up to 7.6 MGy. This is associated with Ce⁴⁺ to Ce³⁺ conversion. Under these irradiation conditions, segregation of SrO to the sample surface was also observed. Further irradiation up to 15 MGy reduced the optical density in the infrared wavelength range between 800-2800 nm due to dissociation of water on the sample surface, activated by radiation damage.