Crystal-field analysis of Er 3+ ions in yttrium aluminium borate (YAB) single crystals

Abstract

Crystal-field energy levels of Er 3+ ions doped in YAB single crystals were fitted to the parameters of semi empirical Hamiltonian including J-mixing. A simulation of the energy level scheme is carried out. The effective Hamiltonian includes elementary interactions such as columbic, spin–orbit, two- and three-body interactions. The crystal-field effect is introduced through the six non-zero crystal-field parameters allowed by D 3 symmetry site occupied by the rare earth. Very satisfactory correlations were obtained between calculated and experimental levels, with root mean square deviation (r.m.s.) of 15.5 cm −1. These results are compared with those reported for Nd 3+ and Dy 3+ ions in the same host and with Er 3+ ions in other hosts. The concordance between the crystal-field strength parameters indicates the consistence of our analyses. The calculated wave functions of the system are used to predict the magnetic g-factors of the 4I 15/2 ground state.