Fixing of volume holograms in ferroelectric K_1−yLiyTa_1−xNbxO_3

Optimal conditions for thermal fixing of volume holograms in Fe:LiNbO3 crystals.

We analyze and compare two typical recording and thermal fixing procedures of a volume hologram in a Fe:LiNbO(3) crystal (low-high-low procedure and high-low procedure). We consider the kinetics of the recording, compensating, and developing processes by taking into account the ratio of the conductivities between the protons and the electrons as a function of temperature. From the analysis the ...

Volume Holograms

Fixing of photorefractive volume holograms in K(1-y)Li(y)Ta(1-x)O(3).

We report the fixing of photorefractive holographic gratings with high efficiency in a sample of K(1-y)Li(y)Ta(1-x)Nb(x)O(3) doped with Cu, V, and Ti. Holograms are thermally fixed through the screening of a photorefractive space-charge f ield by a nonphotoactive species at elevated temperatures. Fixed holograms are revealed by illumination at lower temperatures. Diffraction efficiencies of 25%...

Control of volume holograms

Received May 9, 1991; revised manuscript received February 14, 1992; accepted February 25, 1992 The mismatch in the number of degrees of freedom supported by volume holograms and the boundary fields that control them limits the dynamic range of recorded holograms. For holograms controlled by using fractal sampling grids, the maximum dynamic range falls inversely with the minimum number of expos...

Thermal fixing of 10,000 Holograms in LiNbO3:Fe.

We discuss thermal fixing as a solution to the volatility problem in holographic storage systems that use photorefractive materials such as LiNbO(3):Fe. We present a systematic study to characterize the effect of thermal fixing on the error performance of a large-scale holographic memory. We introduce a novel, to our knowledge, incremental fixing schedule to improve the overall system fixing ef...