Spectroscopic properties and location of the Ce3+ energy levels in Y3Al2Ga3O12 and Y3Ga5O12 at ambient and high hydrostatic pressure

Abstract

In this study, we present the high pressure spectroscopy of Y₃Al₂Ga₃O₁₂ (YAGG) and Y₃Ga₅O₁₂ (YGG) ceramics doped with Ce³⁺ and Cr³⁺. We have found that high hydrostatic pressure recovers the Ce³⁺ luminescence in YGG. The pressure-induced shifts of the ground state and the 5d₁ excited state of Ce³⁺ with respect to the conduction band edge were estimated. Our experimental data allowed us to also obtain the shifts of the conduction and valence band edges, and the ground state and the 5d₁ state of Ce³⁺ ions have been estimated with respect to the vacuum level. It has been shown that simple equivalence between the external hydrostatic pressure and intrinsic chemical pressure related to different compositions of the isostructural matrices does not exist in garnet lattices.