Optimization of iron-doped photorefractive lithium niobate crystals

Summary form only given. Photorefractive iron-doped lithium niobate crystals (LiNbO/sub 3/:Fe) are still the best choice for many applications, such as holographic data storage, outstanding interference filtering, or wavelength division multiplexing. Iron occurs in LiNbO/sub 3/ in the valence states Fe/sup 2+/ and Fe/sup 3+/, only. Holographic investigations are performed by an (argon-ion laser) and with near-infrared light (wavelength 760 nm, Ti:sapphire laser). Gratings are recorded by interference of two plane waves. One of the recording waves is blocked and the other one is diffracted from the grating. The amplitude of the refractive-index modulation is calculated from the measured diffraction efficiency.