Abstract

The optical properties of Cu⁺ ions in RbMgF₃ single crystals have been investigated. In this material, two distinct sites are available for the Cu⁺ ions when they replace Rb⁺ host lattice ions. The symmetry of the two Rb⁺ sites is C_3v and D_3h respectively. Therefore, this crystal structure provides the opportunity to study the same ion, Cu⁺, in two different sites in one crystal. Two sets of optical absorption and emission bands are observed. The two sets of optical transitions are guite different in nature. In one case, the optical data suggest that there is very weak coupling between Cu⁺ ions and the lattice, whereas in the other case strong coupling exists. This is evidenced also by the transition lifetimes of the luminescence associated with these centers. The off-center nature of the copper ions in one lattice position give rise to interesting low temperature optical effects. These effects can be explained in terms of weak and strong lattice coupling and can be utilized to yield an energy level diagram for Cu⁺ ions in RbMgF₃.

© 1984 Optical Society of America