Magneto-optical Performance Of Terbium Gallium Garnet Crystal

Polycrystalline synthesis and single crystal growth of Terbium Gallium Garnet crystal were studied in this paper.As-grown TGG crystals were tested and analyzed.TGG polycrystalline was synthesized by chemical co-precipitation method and solid-phase reaction method.The polycrystalline were tested by TG-DSC,X-Ray Diffraction,IR-Spectroscopy,X-ray Photoelectron Spectroscopy,Raman Spectroscopy and Scanning Electron Microscope.Combined with the test results,the optimum process conditions of the two methods were determined.High quality polycrystalline materials were prepared.TGG single crystals which have complete shape have been obtained by Czochralski method.Puling speed was 1-1.5mm/h,rotation speed was 10-15r/min,protective atmosphere was pure N2 or 85%N2+15%CO2.The effects of different process conditions on the crystal quality and defects control in the process of crystal growth were studied.As-grown TGG crystals were directed,cut and polished,X-Ray powder diffraction,transmittance,absorptivity,X-ray photoelectron spectroscopy,Raman spectroscopy,refractive index and extinction ratio were tested.The test results show that the crystal have high purity,large transmittance and refractive index,low absorptivity and extinction ratio.The Faraday rotation angle and Verdet constant of as-grown crystals at the wavelength of 532 nm,632nm and 1064 nm were measured by extinction method.Combined with the absorption coefficient,magneto-optical figure of merit were calculated.The test results show that the crystal have large Verdet constant.The preferred direction of TGG crystal were determined.The influence factors of the Verdet constant of paramagnetic materials were studied.