Nearly 100% diffraction efficiency fixed holograms in oxidized iron-doped LiNbO3 crystals using self-stabilized recording technique

We analyse the advantages and limitations of self-stabilized holographic recording for fixing in photorefractive iron-doped LiNbO3 crystals. We study the effect of the degree of oxidation on the development of the fixed grating, confirm the importance of highly oxidized crystals to obtain fixed holograms with high diffraction efficiency and put it on a quantitative basis. We also discuss the effect of iron-concentration and the way oxidation may introduce dopant-saturation effects in the recording. Accounting on the different parameters here considered we propose a very simple and well performing procedure to produce nearly 100% diffraction efficiency fixed gratings.