The observation of photon cascade emission in Pr3+-doped compounds under X-ray excitation

Abstract The problem of obtaining two visible photons from a single incident vacuum ultraviolet photon is considered and conditions of cascade emission observation in various Pr 3+ -activated compounds are reviewed. Hosts with weak crystal field, low phonon energies, large band gap, large cation–anion distance, and large coordination number for the substitution site are desirable. Emission spectra and decay curves under X-ray excitation of some Pr 3+ -doped materials: LaAlO 3 , LaMgAl 11 O 19 , SrAl 12 O 19 and SrAlF 5 have been measured. Photon cascade emission has been observed in SrAl 12 O 19 :Pr 3+ and SrAlF 5 :Pr 3+ . The influence of the Pr 3+ concentration on the emission has been studied in SrAl 12 O 19 :Pr 3+ . Intrinsic (excitonic) luminescence, which has an adverse effect on the cascade emission, is usually suppressed in compounds containing 0.5 or more percent of Pr 3+ .