Optical transitions intensities of Dy3+:Y4Al2O9 crystals

Spectroscopic properties of trivalent dysprosium (Dy3+) activated Y4Al2O9 (abbreviated YAM) crystals have been investigated. The Judd–Ofelt formalism has been applied to the analysis of the room temperature absorption spectrum. The calculated radiative lifetime of the 4F9/2 state is in a very good agreement with the measured one. Branching ratios were obtained from emission spectrum and used in modified Judd–Ofelt method calculations. Concentration dependent fluorescence dynamics profiles have been investigated in Dy3+:YAM to understand better processes responsible for concentration quenching of the dysprosium 4F9/2 emission. The cross-relaxation transfer rates were experimentally determined as a function of Dy3+ concentration. Decays were modelled using Inokuti–Hirayama approach to obtain an information on the energy transfer mechanism. The lasing properties of Dy3+:YAM have been discussed.

► Spectroscopic and lasing properties of Dy3+:Y4Al2O9 crystals are investigated.
► Judd–Ofelt formalism is applied to analyze the RT absorption spectrum.
► Concentration dependent fluorescence dynamics are investigated.
► Quenching rates are determined as a function of Dy3+ concentration.
► Decays are modelled using Inokuti–Hirayama approach.