Optimal Recording Wavelength for Nonvolatile Photorefractive Holograms in Ce:Cu:LiNbO

Three wavelengths of red, green and blue of recording beams are systemically tested for the UV-assistant recording and optical fixing
of holograms in a strongly oxidized Ce:Cu:LiNbO₃ crystal. Three different hotorefractive phenomena are observed. It is shown that the green beams will optimally generate a critical strong nonvolatile hologram with quick sensitivity and the optimal switching technique could be jointly used to obtain a nearly 100% high diffraction. Theoretical verification is given, and a prescription on the doping densities and on the oxidation/reduction states of the material to match a defined recording wavelength for high diffraction is suggested.