Effect of annealing in two-center holographic recording

Abstract

The initial electron concentration of Mn and Fe traps in lithium niobate crystals has a significant impact on the performance of the crystals for two-center holographic recording. The energy-band diagram is presented for a typical LiNbO3 crystal doped with Fe, and Fe and Mn. The absorption spectra for the differently annealed crystals LN1, LN3, and LN4 were analyzed before sensitization, subtracting the effect of Fresnel reflections from the spectra. The absorption spectra for the crystal LN3 were also analyzed before and after ultraviolet illumination with an intensity of 4 W/cm2. The variation of the persistent M/# was examined with the portion of filled Mn traps for a LiNbO3 crystal doped with 0.075 wt % Fe2O3 and 0.01 wt % MnO.