Decay of the luminescence from Cr³⁺ ions in mixed-cation β-aluminas

Decay of the luminescence from Cr³⁺ ions in Na_1-xK_x β-aluminas has been measured to analyze systematically the structure of the conduction plane in mixed-cation β-aluminas. All decay curves obtained can be represented by the combination of an empirical decay-function (I(t) ~ exp{- (t/τ)^α}. From the concentration dependence of the parameter α, which characterizes the decay function, the disordered nature of the conduction plane was discussed with the mixed-alkali effect.