Electron-lattice coupling in congruent Co-doped LiNbO3 : Cr3+: ZnO crystal

The importance of the role of the ion-lattice coupling in determining the e nergy levels of Cr3+ ions in congruent LiNbO3 crystals doped with 2.9% of Z nO is demonstrated in this paper. The Racah parameters: B = 533 cm(-1), C = 3244 cm(-1) and the crystal-field intensity Dq = 1527 cm-1 were determined and the Tanabe-Sugano diagram was constructed. The characteristics of the absorption and the emission spectra of Cr3+ ions in these crystals can be e xplained in terms of the configurational-coordinate diagram in the harmonic approximation, with good agreement obtained. The Huang-Rhys parameter S = 6.86 and the lattice phonon energy (h) over bar omega = 343 cm(-1) are also reported in this work.