Study On Growth And Holographic Properties Of Zirconium Copper Iron Triple-doped Lithium Niobate With Various Ratio Of Lithium And Niobium

In recent years, with the rapid development of information technology and the advent of the era of big data, higher requirement was put forward for data storage capacity and transmission rate. Holographic storage technology, which is just with these two distinctive advantages, has always been the focus of domestic and foreign research institutions’ and corporate research. As a potential volume holographic storage material, doped lithium niobate has been extensively studied.In this paper, a series of Zr:Cu:Fe:Li Nb O3 crystals with various ratios were studied. The growth and processing procedure were introduced systematically; the site situation of the dopant ions in the crystals was illuminated; the effect of dopant ions on holographic storage technology was tested and analyzed; which supplied experimental evidence and theoretical guidance for the development of materials with excellent volume holographic storage performance.Firstly, Zr:Cu:Fe:Li Nb O3 crystals with various ratios were grown by Czochralski method, whose [Li]/[Nb] ratios were 0.946、1.05、1.2 and 1.38 respectively. And the grown crystals were cutted using inner circle cutting machine and polished by a polishing machine.Secondly, the crystal defects were tested through the X-ray powder diffraction, infrared transmission and ultraviolet absorption spectrums. The formation mechanism of the changes in cell parameters and the shift of infrared absorption peak and ultraviolet spectrum absorption edge were analyzed. The tests above shows that the addition of Zr, Cu and Fe does not damage the fundamental structure of the crystals. With the [Li]/[Nb] ratio increasing, the OH- absorption peaks present a violet shift and a peak appears at 3468 cm-1, which indicates a near stoichiometric component, when [Li]/[Nb] ratio is 1.05. The ultraviolet absorption edge shifts to shorter wavelength at first and then in reverse.Thirdly, the diffraction efficiency, writing and erasing time of the crystals were tested by two-wave coupling optical experiments; and the photorefractive sensitivity, and dynamic range were calculated according to the data obtained. With the increase of [Li]/[Nb] ratio, the diffraction efficiency increases at the beginning then decreases, the photorefractive sensitivity is just the opposite compared with diffraction efficiency and the dynamic range increases gradually. At the same time, the non-volatile storage performance was tested using two-photon storage experiment.At last, the resistance ability to light scattering of the crystals was tested using transmission facula distortion method. With the increasing of [Li]/[Nb] ratio, it increases at first and then decreases.