DUAL LUMINESCENCE OF CU+ IN GLASS

Absorption, emission and excitation spectra of Cu+ ((2.528 ± 0.25) × 1018 ions/cm3) in a glass of near pure silica (96%) composition have been measured. It is suggested that the spectral data are consistent with Cu+ ions in octahedral coordination of oxygen in the silica network. The two observed emitting states (∼ 450 nm and ∼ 490 nm), each of which has been characterized as triplet (3Eg), are ascribed to the existence of two relatively predominant slightly different copper(I) sites with the same coordination. The bi-exponential nature of each emitting state on the other hand is assumed to be the result of splitting of the triplets due to spin-orbit interaction. © 1990.