A stochastic analysis of the luminescence decay of Cr(III) in diopside

The luminescence decay curves of the Cr(III) ion in natural diopside crystal [(Ca,Mg)1−n(Na,Mn,Al,Cr)1+nSi2O6] are analyzed within the framework of stochastic modelling. The existing model describes the relaxation process as the integrated second-order Markov chain, IAR(2,1,0). The purpose of this work is to obtain additional information about the deactivation mechanisms resulting from the intra- and inter-ion couplings giving rise to the quasi-periodicity of the decay functions. We show that the decay process is characterized by the coherency being represented by the non-zero autocorrelation function and by the vanishing oscillation with fixed quasi-period and damping parameters. The memory time of the process IAR(2,1,0) has been introduced as a new characteristic of the luminescence decay.