The Steady-state and Transient Characteristic Analysis of Thermal Fixing a Photorefractive Hologram Grating in Lithium Niobate
نویسندگان
چکیده
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 diffusionand 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.
منابع مشابه
Electrical fixing of photorefractive holograms in Sro . 7 5 Bao . 25 Nb 2 O 6
Volume holograms recorded in photorefractive materials can find important applications in optical memories and optical computing systems. One problem with a photorefractive hologram is that it gets erased by the readout light. Nondestructive readout can be achieved by hologram fixing, and several fixing methods have been reported. Thermal fixing of holograms was demonstrated in LiNbO3,' Bi1 2Si...
متن کاملHolographic storage dynamics in lithium niobate: theory and experiment
We present a theoretical model that describes holographic ionic fixing and storage dynamics in photorefractive crystals. Holographic gratings that are based on charge redistribution inevitably decay because of ionic and electronic conduction. Relevant decay rates and transient hologram field expressions are derived. Ionic gratings are partially screened by trapped electrons on readout. The life...
متن کاملOptimal 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 ...
متن کاملTemperature dependence of absorption in photorefractive iron-doped lithium niobate crystals
We present experimental data showing a significant dependence of light absorption on temperature in photorefractive LiNbO3 :Fe crystals. The results are successfully explained by assuming that the widths of the Fe absorption bands in the visible and in the infrared spectral region depend on temperature. The findings are of relevance for thermal fixing of holograms. Furthermore, a temperature-in...
متن کاملX-ray-induced conductivity in iron-doped lithium niobate crystals
Illumination of photorefractive, iron-doped lithium niobate crystals (LiNbO3 :Fe) with x-rays generates a conductivity that we determine from the speed of hologram erasure. The doping levels of the crystals and the acceleration voltage of our x-ray tube are varied. A theoretical model is presented, which describes the obtained results. A decrease of the conductivity with increasing Fe concentra...
متن کامل