The paper presents the results of a study of the luminescent properties of calcium gallate activated by trivalent rare earth ions Yb3+ and Er3+. IR luminescence spectra of samples with a single activator Ca1‑хYbxGa2O4,Ca1‑хErxGa2O4 were studied when excited by radiation sources with a wavelength of 940 and 790 nm, respectively. The dependence of the luminescence intensity of samples on the concentration of rare earth ions is obtained. When the two-activator composition of Ca1‑х‑yYbxEryGa2O4 is excited by a semiconductor laser diode with a wavelength of 940 nm, IR luminescence is registered in the regions of 980-1100 nm and 1450-1670 nm. The radiation in these bands corresponds to electronic transitions in Yb3+ and Er3+ ions, respectively. For a luminescence band with a maximum at a wavelength of 1540 nm, the excitation spectra were measured, the maximum intensity is at the wavelengths: 930, 941, 970, 980 nm. The dependence of the IR luminescence intensity of a solid solution of Ca1‑х‑yYbxEryGa2O4 on the concentration of Er3+ ions was studied. With an increase in the concentration of Er3+ ions in the luminescence spectra, there is a redistribution in the intensity of the bands belonging to Yb3+ and Er3+ ions, which indicates the presence of energy transfer processes between these ions. The kinetics of IR luminescence attenuation was studied for series with one and two activators: Ca1‑хYbxGa2O4,Ca1‑хErxGa2O4, Ca1‑х‑yYbxEryGa2O4. It is established that the luminescence attenuation occurs mainly according to the exponential law, which indicates the predominance of the intracenter luminescence mechanism in the studied structures. Based on the analysis of the excitation and luminescence spectra of experimental samples, conclusions are made about the interaction of Yb3+ and Er3+ activator ions in the crystal lattice of calcium gallate.
Kinetics of luminescence calcium gallate activated by Yb3+, Er3+ ions
