Luminescence and defect studies of YAlO _3:Dy ~(3+), Sm ~(3+) single crystals exposed to 100 MeV Si ~(7+) ion beam

摘要

Ionoluminescence (IL) and photoluminescence (PL) spectra for different rare earth ions (Sm ~(3+) and Dy ~(3+)) activated YAlO _3 single crystals have been induced with 100 MeV Si ~(7+) ions with fluence of 7.81×10 ~(12) ions cm ~(-2). Prominent IL and PL emission peaks in the range 550-725 nm in Sm ~(3+) and 482-574 nm in Dy ~(3+) were recorded. Variation of IL intensity in Dy ~(3+) doped YAlO _3 single crystals was studied in the fluence range 7.81×10 ~(12)-11.71×10 ~(12) ions cm ~(-2). IL intensity is found to be high in lower ion fluences and it decreases with increase in ion fluence due to thermal quenching as a result of an increase in the sample temperature caused by ion beam irradiation. Thermoluminescence (TL) spectra were recorded for fluence of 5.2×10 ~(12) ions cm ~(-2) on pure and doped crystals at a warming rate of 5 °C s ~(-1) at room temperature. Pure crystals show two glow peaks at 232 (Tg _1) and 328 °C (Tg _2). However, in Sm ~(3+) doped crystals three glow peaks at 278 (Tg _1), 332 (Tg _2) and 384 °C (Tg _3) and two glow peaks at 278 (Tg _1) and 331 °C (Tg _2) in Dy ~(3+) was recorded. The kinetic parameters (E, b s) were estimated using glow peak shape method. The decay of IL intensity was explained by excitation spike model.