Behavior of the Structural and Dielectric Characteristics of (Pb0.89Ba0.11)5Ge3O11 Single Crystals under Irradiation with High-Energy Electrons

Stoichiometric (Pb0.89Ba0.11)5Ge3O11 single crystals have been grown under conditions of slow melt cooling. The influence of irradiation by high-energy (10 MeV) electrons on the structural and dielectric characteristics of these crystals has been studied for the first time. The paraelectric structure of the crystals (sp. gr. P 6̅ ) is found to retain at 293 K after the irradiation. The influence of a lone electron pair on the substitution of Pb for Ba is found. Despite the irradiation with a fluence up to 6.2 × 1018 cm–2, (Pb0.89Ba0.11)5Ge3O11 single crystals retain their structural quality. Temperature dependences of the permittivity and dielectric loss (in the temperature range of 5–300 K and the frequency range of 1–1000 kHz) indicate that the irradiation shifts the Curie point from 123 to 95 K and increases broadening of the ferroelectric phase transition.