Photon Cascade Luminescence of Pr3 + in LaMgB5 O 10

The observation of photon cascade emission in Pr 3+ activated LaMgB 5 O 10 under 185 nm vacuum ultraviolet excitation is reported and discussed. In this host lattice, the lowest energy state of the Pr 3+ 4f5d excited configuration is located above the 1 S o state. The excitation of the 4f5d state by vacuum ultraviolet photons results in radiative emission originating from the 1 S o level state. The absence of emission from the 3 P o state is attributed to the efficient multiphonon 3 P o → 1 D 2 relaxation in this lattice.