C# application for determining the probabilities of radiative transitions from individual components of the excited level 4F3/2 of the Nd3+ ion based on the temperature dependence of the lifetime

In this paper, a theoretical description of the experimental dependence of the lifetime of the excited 4F3/2 multiplet of the Nd3+ ion in the LiYF4 crystal is obtained, and a method for determining the probabilities of transitions from individual Stark components of the excited level is proposed. An application in C# with a user-friendly interface has been developed for computer modeling of the temperature dependence of the lifetime of the excited level 4F3/2 of the Nd3+ ion in the LiYF4 crystal. On the main form, it is necessary to enter the energies of the Stark components of the excited multiplet and all the underlying ones, the luminescence branching coefficients, and the experimental data on the temperature dependence. Using only two variable parameters, good agreement was obtained between the calculated and measured lifetime graphs in the temperature range from 10 K to 300 K. The use of the developed application made it possible to determine for the first time, based on the temperature dependence, the probabilities of radiative transitions from each Stark component of the 4F3/2 multiplet: from the underlying component (energy 11393 cm-1) the probability is 1755 s-1, from the overlying component (energy 11472 cm-1) the probability is 2457 s-1. The proposed algorithm for calculating the probability of a radiative transition from each Stark component of the excited multiplet based on the results of computer modeling of the temperature dependence of the lifetime significantly increases the information content of experiments on measuring the temperature dependence of the lifetime.