An optical study of the stretching absorption band near 3 microns from OH- defects in LiNbO3

Growth and spectroscopic characterization of Zr:Fe:LiNbO3 crystals with various Li/Nb ratios

“…3 shows the UV-vis absorption spectra of the crystals. The absorption edge of LiNbO 3 crystals is used to determine the composition [23]. The blue edge of optical absorption at the level 20 cm À 1 is widely used for the characterization of the Li/Nb ratio in a crystal [24].…”

Holographic storage dynamics in lithium niobate: theory and experiment

“…It is well established 19,25 that the ionic conductivity in as-grown and hydrogen-doped LiNbO 3 crystals is predominantly due to the H ϩ ions. Hydrogen normally is located in the oxygen planes along the O-O bond, and its relative contents can be evaluated therefore as the strength (peak or integral) of the OH Ϫ stretching vibration absorption line near 2.87 m. 26 Vormann et al 19 showed unambiguously that in as-grown and H ϩ -doped crystals the ionic conductivity is due to hydrogen and deduced the activation energy of E a ϭ 1.2 eV for its migration. It was recognized, however, that in asgrown LiNbO 3 the residual ionic conductivity gives an extrapolated lifetime of an ionic hologram of only 50-70 days at room temperature, and therefore increasing the available storage time requires a substantial reduction of ion density.…”

The OH− absorption spectra of low doped lithium niobate crystals

“…For nominally pure LiNbO 3 crystals, the components of the OH À absorption band have been discussed for a long time. Two-peak, threepeak, four-peak, and five-peak models have been proposed [5][6][7][8], and the four-peak model had been generally accepted for a long time. Recently, nearly stoichiometric LiNbO 3 has been successfully grown [9][10][11].…”