De-excitation processes of optically excited Nd3+ pairs in CsCdBr3

Abstract

International audienceCsCdBr3 : Nd3+ crystals have been studied by laser selective excitation and time resolved spectroscopy. Due to the charge compensation resulting from the Nd3+ / Cd2+ substitution, the proportion of Nd3+ pairs is very large and does not follow the statistical laws. This proportion has been measured, its variation with concentration has been established and the effect of codoping with a monovalent metal observed. From a comparison between the properties of single ions and pairs, energy transfers have been analysed. De-excitation channels have been determined for some excited levels from the dynamics and the relative intensities of luminescence lines. An unusual behaviour, which can lead to applications, has been observed : the 4F3/2 luminescence of pairs if favoured with respect to that of single ions. This behaviour is well explained