Optical properties of LiNbO3 crystals doped with Yb3+ ions.

Optical properties of Yb-doped LiNbO3 crystals were investigated. The low temperature absorption and selective emission of LiNbO3:Yb3+ crystals obtained by Montoya et al were reexamined. The LiNbO3:Yb3+ crystals absorption and emission spectra show broad emission due to the presence of four non-equivalent sites: three octahedral sites (Li+ (S1), Nb5+(S2), and a vacant octahedron(S3)) and an interstitial tetrahedral site(S4). Considering the presence of these four Yb3+ion-occupied sites, and also the electron-phonon coupling processes, the majority of emission and absorption lines was assigned. For the different observed optical centers in LiNbO3, the experimental Stark energy levels of Yb3+ ions were established. [ABSTRACT FROM AUTHOR]