Eu2+-doped CsBr photostimulable X-ray storage phosphors — analysis of defect structure by high-frequency EPR

Abstract

Eu 2+-doped CsBr in form of needle image plates is a promising alternative to the granular Eu 2+: BaFBr X-ray storage phosphor with respect to photo-stimulated luminescence, yield and spatial resolution. However, in order to understand the corresponding mechanisms on an atomic scale, the defect structure of Eu 2+-doped CsBr photostimulable X-ray storage phosphors has to be analyzed. By means of high-frequency electron paramagnetic resonance (EPR) spectroscopy, three types of defects have been observed — an electrically neutral dimeric [Formula: see text] defect complex and a neutral trimeric [Formula: see text] defect complex (FZ-center), as well as acceptor-type F-centers [Formula: see text] that are generated by the trapping of electrons at initially neutral bromine vacancies.