Luminescence properties of scintillators in soft X-ray region

Both the total luminescence yield (TLY) and the luminescence spectra of scintillators were measured to identify which scintillator exhibited high luminosity in the soft X-ray (SX) region from 300 eV to 1.3 keV. The TLY intensities and the peak intensities of the luminescence spectra were compared to identify the scintillators that have high luminosity for reducing the pixel size of a two-dimensional detector by applying the stimulated emission depletion phenomenon. The obtained TLY intensities were Tl:CsI, Eu:GGG, Ce:LYSO, Tb:LSO, Eu:YAP and Ce:YAP (in descending order of strength), which differs from the known luminosities in the hard X-ray region. The order of the measured TLY intensity and the change of order between the present and the previous values of luminosities can be explained by the number of secondary electrons generated in the base material of the scintillator in the SX region.