Photon cascade luminescence in CaAl12O19:Pr, Cr

In this report, the Cr3+ ion was chosen as a co-dopant to modify the unpractical photon cascade emission properties of Pr3+-doped CaAl12O19 phosphors, which emit one near-UV photon from the 1S0 state followed by visible photons from the 3P0 state, into phosphors that emits two visible photons through energy transfer. The photon cascade emission process via energy transfer and the transfer mechanisms were systemically investigated by luminescence spectra and dynamics using synchrotron radiation as one of the excitation sources. The internal visible quantum efficiency of CaAl12O19:Pr, Cr was estimated and compared with CaAl12O19:Pr and the drawback to obtain the visible quantum efficiency higher than unit for CaAl12O19:Pr, Cr as a practical VUV phosphor was also discussed.