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This work is devoted to examining the influence of energy transfer processes between Ce3+ and Pr3+ ions on the luminescent and scintillation properties of LuAG:Ce and LuAG:Ce,Pr scintillators, grown by liquid phase epitaxy onto undoped LuAG substrates with a PbO–B2O3-based flux. To characterize them, measurements of the absorption, cathodoluminescence, photoluminescence emission and excitation spectra as well as the photoluminescence decay kinetics of the SCFs under study were performed. The investigation confirmed simultaneous energy transfer processes between d-f and f-f states of Pr3+ ions and between Pr3+ (d-f) and Ce3+ (d-f) ions, as well as from Ce3+ (d-f) to Pr3+ (f-f) ions in LuAG host. Furthermore, the energy transfer from Pb2+ flux-related impurity to Ce3+ (d-f) and Pr3+ (f-f) ions also were found in the LuAG:Ce and LuAG:Ce,Pr SCFs. An energy diagram of the Pb2+, Pr3+ and Ce3+ ion levels was constructed, which provides a deeper overview of the mentioned energy transfer processes.

Thermoluminescence (TL) often involves the liberation of a charge carrier (an electron or a hole) from a charge carrier trapping centre into the conduction band (CB) or the valence band (VB) with subsequent recombination with a counter charge carrier at a luminescence centre. TL glow peak analysis can provide the energy ΔEt needed to liberate such charge carrier which then defines the location of the charge transition levels (CTL) of the carrier trapping centres below the CB-bottom or above the VB-top. The temperature at the maximum of the TL glow peak changes 3–4 K per 0.01 eV change in ΔEt thus providing an extremely sensitive probe of energy changes in CTLs. This work collects and reviews data on glow peaks due to electron or hole release from lanthanide dopants in 36 different inorganic compounds. To compare results from different literature sources, data were always re-analysed using the same method that is solely based on the temperature at the maximum of the glow peak. The changes in ΔEt along the lanthanides series provides insight at the sub 0.1 eV level on the changes in CTL energies. We will use a compound-dependent parameter to account for the nephelauxetic effect and a compound dependent parameter to account for lattice relaxation around the lanthanide. Together with information from lanthanide luminescence spectroscopy, the vacuum referred binding energy (VRBE) diagram will be constructed for each compound. The lanthanide electron or hole trap depth read from the VRBE scheme will be compared with that derived from the TL glow peak. Surprisingly good agreement will be demonstrated.

For the past few decades, fibre-optic dosimeters (FODs) have been a focus of research for dosimetry with LINACs, owing to a unique set of advantageous qualities: compact dosimeter sizes, an all optical composition (i.e. no wires or electronics around their sensitive volume), real-time response proportional to the absorbed dose-rate in their sensitive volumes and direct water equivalence. Such a set of qualities makes FODs “near-correctionless” for dosimetry with LINACs, such that they have been recommended as in vivo dosimeters and small field dosimeters. Further, their scintillation and luminescence response mechanisms are not affected by magnetic fields. Given this set of qualities, FODs are attractive candidates for dosimetry with MRI-LINACs. This mini-review aims to provide an overview of FODs to the wider medical physics community, and present the current challenges and opportunities for FODs given previous investigations into MRI-LINAC dosimetry.

This work is dedicated to the growth process and investigation of luminescent and scintillation properties of CeAlO3 single crystals and CeAlO3/CeAl11O18 metamaterials under e-beam and α-particles excitation. It has been shown that cathodoluminescence and radioluminescence spectra of CeAlO3 crystals contain two bands, peaking at 440 and 500 nm, and caused by the Ce3+ 5d−4f transitions into CeAl11O18 phase, which is present in these crystals as an admixture. Under 270 nm ultraviolet (UV) light excitation, a CeAlO3 crystal possesses complicated non-exponential luminescence decay, with the average decay time of 16 ns. The light yield of CeAlO3 crystals under α-particle excitation is about 16% and 12%, in respect to the standard Bi4Ge3O12 (BGO) crystal and Y3Al5O12:Ce (YAG:Ce) single crystalline film samples, respectively. The CeAlO3 scintillation decay is quite fast, with the decay time value t1/e in the 54−56 ns range.