Spectroscopic analysis of Nd3+ pairs in CsCdBr3

Abstract

In Nd3+ -doped CsCdBr 3 crystals, most of the Nd3+ ions form pairs. A detailed analysis of the optical spectroscopy of these pairs has been carried out using both absorption and luminescence spectra. Due to the low value of the Debye cutoff frequency for the phonons, many excited.1evels are luminescent, thus giving a lot of spectroscopic information and allowing the assignment of 65 levels to their associated irreducible representations. These results have been used to deduce, through a fitting procedure, the free-ion and crystal-field parameters. The results are discussed and compared with those found in other compounds.

Crystal growth, upconversion, and infrared emission properties of Er3+-doped KPb2Br5

“…Therefore, it appears unlikely that the emission lines observed above 1600 nm originate from isolated Er 3+ centers. The existence of different Er 3+ sites and possibly Er 3+ -pair centers in KPB, as observed for REdoped CsCdBr 3 [41,42], will be further explored in future investigations.…”

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

“…For the present work, it is sufficient to know approximately the position of some energy levels which are shown in figure la. [10]. This observation has been interpreted as arising from two Nd3 + species : i) ions having a nearby Nd3 + ion and forming a pair with it ; ii) other ions [12].…”

“…It will be published elsewhere [10]. In [10]. For the present work, it is sufficient to know approximately the position of some energy levels which are shown in figure la.…”

“…As only few spectroscopic results are known, a comprehensive analysis of energy level positions has been completed. It will be published elsewhere [10]. In [10].…”

“…For all these crystals, the pair line, observed at short time after the laser pulse, remains the largest line by two orders of magnitude. Spectrum Using the detailed energy level scheme [10], it is possible, considering only one phonon processes and supposing a cutoff frequency equal to 90 cm-l, to find that for 4G5/2 the quenching processes are : with 13 possibilities for (i, j) and with 10 possibilities for (i, j). They are illustrated in figure lb.…”