Theoretical investigation of a single erbium center in hexagonal gallium nitride

A theoretical energy-level analysis was based on parametric Hamiltonian for the 4f11 electronic configuration of Er3+ ions in C3v center, and it permitted a phenomenological characterization of crystal-field (CF) Hamiltonian parameters. This characterization allowed us to calculate the energy of the missing stark levels of the 4I15/2 and 4I13/2 states and to confirm the presence of a single emission center with C3v symmetry. The calculated CF and strength parameters are compared with those obtained for Sm3+, Pr3+ and Yb3+ ions in the same host and with Er3+ in other isostructural hosts.