<title>Radio- and VUV-excited luminescence of YAP:Ce, YAP:Pr and YAG:Pr</title>

Abstract

In this Communication we report initial results of studies on X-ray and VUV excited luminescence of YAP and YAG crystals activated with Pr3+, and YAP activated with Ce3+. Excitation and luminescence spectra of Pr 3 + and Ce 3+ d-f and Pr 3 + f-f emissions and luminescence time profiles under pulsed synchrotron excitation are presented and analysed in order to identify and characterize various host-to-ion energy transfer channels. The results support the notion that direct and trap mediated capture and recombination of holes and electrons via Pr 3` or Ce 3 + ions provide the dominant mechanism of radioluminescence production in both YAP and YAG crystals.

Luminescence and scintillation properties of YAG:Pr

“…The probability of this transfer is very low at 10 K and increases with temperature. In the case of VUV excitation, the -emission is a result of not only a transfer described above but also most probably a direct energy transfer from e-h pairs [7]. This explains the -emission existence at low temperature.…”

“…The origin of the first one is probably associated with contamination by Gd ions. It is most likely, due to the transition from the P to S levels of Gd 4 configuration [7]. The other lines are well known and are due to forbidden Pr -transitions [8].…”

“…Under VUV excitation at both temperatures and for -excitation at 300 K, the intensities ofbands are relatively large, while at 10 K under direct -excitation, they are very weak. In the case of direct -excitation, in consequence of a relatively low -energy gap (of about 10 000 cm ), the -emission is most probably subsequent to a nonradiative energy transfer from 4 5 to P levels [7]. The probability of this transfer is very low at 10 K and increases with temperature.…”

Bright Cathodoluminescent Thin Films for Scanning Nano-Optical Excitation and Imaging

“…Additionally, the spectra and lifetimes of photoluminescence from films were measured and closely resemble those of bulk YAP:Ce (Supporting Information Figures S6 and S7). 49 Thus, the YAP:Ce films possess the requisite crystal structure, composition, and quality that are critical to obtaining bright cathodoluminescence with the desired spectral character.…”

Preparation of thin films of perovskite-type YAlO 3 :Gd 3+ –Pr 3+ UV phosphors

“…Accordingly, perovskite-type oxides showing UV emission were hardly investigated except for YAlO 3 :Ce 3+ and YAlO 3 :Pr 3+ [17,18]. Nevertheless, because such materials may have interest for future medical or sanitary applications [19,20], we have conducted a material survey on UV emission phosphors in perovskite-type oxides.…”