Crystal growth and optical properties of gadolinium aluminum garnet

Recent progress in advanced optical materials based on gadolinium aluminate garnet (Gd3Al5O12)

“…Earlier studies by Mizuno et al [9–13] on the phase diagram of Ln 2 O 3 –Al 2 O 3 found the two intermediate compounds of Ln 2 O 3 ·11Al 2 O 3 ( β -Al 2 O 3 type) and LnAlO 3 (commonly referred to as aluminate perovskite or LnAP, an orthorhombic modification of ideal perovskite) for the large ions of La 3+ –Nd 3+ , the two compounds of LnAP and monoclinic Ln 4 Al 2 O 9 (commonly called LnAM) for the intermediately sized Sm 3+ –Gd 3+ , and the three compounds of LnAM, LnAP, and LnAG for the small Ln 3+ ions of Tb 3+ –Er 3+ . Though GdAG (further abridged as gadolinium aluminate garnet (GAG) hereafter) was not identified in the work of Mizuno et al , it was successfully synthesized via flux growth by Van Uitert et al [14] and Manabe and Egashira [15] for potential optical applications. Later on, Shishido et al [16] found via annealing Gd 2 O 3 ·5/3Al 2 O 3 amorphous glass that GAG is metastable and would completely decompose to α -Al 2 O 3 and GdAP (Gd 3 Al 5 O 12 → Al 2 O 3 + 3GdAlO 3 ) upon prolonged annealing at 1500 °C.…”

Preparation of Cerium-Activated GAG Phosphor Powders

“…13 In previous studies, GAG powder was prepared by quenching the glass-crystallized product from a PbO or PbF 2 flux at a high temperature; however, the purity of the product was not described. 14,15 Matyusheuko et al indicated that it is impossible to prepare GAG powder by the solid-state method. 16 Cockayne et al attempted to use the melt-growth method to prepare Gd-rich YAG, but the work was unsuccessful.…”

Scintillation properties of Ce doped Gd2Lu1(Ga,Al)5O12 single crystal grown by the micro-pulling-down method

“…Such crystals have been only obtained by the flux growth method. [14] Recently, transparent Ce:(Gd,Y) 3 Al 5 O 12 optical ceramic with scintillation response of about $90 ns at emission around 550 nm, prospective g-excited light yield of about 11-16,000 photon/MeV and density of 6.0 g/cm 3 were reported [15,16]. Interestingly, extremely high light yield up to 80,000 photon/MeV was reported for b-excitation, which point to very high intrinsic efficiency of such Gd-admixed garnets.…”