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A nonvolatile recording scheme is proposed using LiNbO 3 :Ce:Cu crystals and modulated UV light to record gratings simultaneously in two centres and using red light to bleach the grating in the shallow centre to realize persistent photorefractive holographic storage. Compared with the normal UV-sensitized nonvolatile holographic system, the amplitude of refractive-index changes is greatly increased and the recording sensitivity is significantly enhanced by recording with UV light in the LiNbO 3 :Ce:Cu crystals. Based on jointly solving the two-centre material equations and the coupled-wave equations, temporal evolutions of the photorefractive grating and the diffraction efficiency are effectively described and numerically analysed. Roles of doping levels and recording-beam intensity are discussed in detail. Theoretical results confirm and predict experimental results. [ABSTRACT FROM AUTHOR]

A photorefractive hologram can be fixed locally under a temperature nonuniform field by CO2 laser heating the LiNbO3. Here, on the basis of analyzing the relationship between the fixed space-charge field amplitude Esc and the fixing temperature Tf, two parameters, the localization coefficient Ψ and the average space-charge field amplitude Escave, are defined to evaluate the fixed local photorefractive hologram by CO2 laser heating the LiNbO3. The same analysis also can be used when the boundary conditions and the laser beam profile are changed. © 2000 John Wiley & Sons, Inc. Microwave Opt Technol Lett 26: 89–93, 2000. [ABSTRACT FROM AUTHOR]

Based on Moharam's field modulation function and the coupled-wave equations, exact analytic straight and parametric expressions are deduced for the steady state of dynamic two-beam coupling with any constant values of light intensity modulation and light excitation efficiency. © 2000 John Wiley & Sons, Inc. Microwave Opt Technol Lett 25: 278–283, 2000. [ABSTRACT FROM AUTHOR]

The transient interaction between a refraction index grating and light beams during simultaneous writing and thermal fixing of a photorefractive hologram is investigated. With a diffusion- and photovoltaic-dominated carrier transport mechanism and carrier thermal activation (temperature dependent) considered in Fe:LiNbO3 crystal, from the standpoint of field–material coupling, the theoretical thermal fixing time and the space-charge field buildup, spatial distribution, and temperature dependence are given numerically by combining the band transport model with mobile ions with the coupled-wave equation. ©1999 John Wiley & Sons, Inc. Microwave Opt Technol Lett 23: 372–376, 1999. [ABSTRACT FROM AUTHOR]

We demonstrate a new approach to achieve optical shuffle interconnection by employing a photorefractive crystal plate in which some required holograms have been recorded and fixed in terms of holographic phase grating. The processes of beam recording, fixing, and reproduction art, described, and an implementation scheme for 1D and 2D shuffle is also proposed. The results of proof-of-principle experiments in one and two dimensions are also presented. [ABSTRACT FROM AUTHOR]