Concentration Effects Manifesting Themselves in the Luminescence of Tm3+ Ions in an Oxychloride Matrix

We investigated the luminescence characteristics of Tm³⁺ ions depending on their concentration in an oxychloride matrix. We measured luminescence spectra, luminescence excitation spectra, concentration dependences of the intensity and kinetics of various luminescence bands of rareearth ions of the visible and IR ranges at different excitation wavelengths. We carried out calculations of the concentration dependences of the quantum yield of luminescence: total and individual spectral bands. The crossrelaxational nature of concentration effects in the luminescence of rareearth ions is discussed.