| LiCAF as a tunable laser host has been aroused much attention from scholars in the past decades. Up to the presest, UV spectrum properties and gowth method of Ce:LiCAF has been widely reported by literatures, which prove Ce:LiCAF has potential use in all-solid LD pumped UV laser. At the same time, luminescence and scintilla property of LiCAF doped transition or rare earth ion is investigating by more and rmore institutions. So far, doped LiCAFcrystals have attracted a lot of attentions as potential material for optical components in VUV, fast scintillators, thermoluminescent dosimeters and laser hosts. On the other hand, pure LiCAF crystal has many advantages as primary candidates UV window materials, because of its'unique properties, such as a large band gap, small birefringence, stabilization and high UV/VI transparency. However, many difficulties exist in crystal growth of pure and doped LiCAF, limiting the utility of these crystals. First, it lacks effective technologic method to obtain the rigorous anhydrous LiCAF and Ce:LiCAF polycrystalline material. Second, diffculty of safe gas handling is used to Controlling the growth atmosphere to avoid the melt oxygenation and volatilization in the process. Last, There is a notable di?erence in the linear thermal expansion coe?cient along the a-axis and along the c-axis of LiCAF and Ce:LiCAF crystals. It suggests that large diameter LiCAF and Ce:LiCAF crystals are dicult to grow from the melt because of thermal stress inside the grown crystals. The growth of LiCAF and Ce:LiCAF single crystals by modified Bridgman process in nonvacuum atmosphere is described in the present work. According to exploring the optimal growth conditions, High optical performances characterized by transmission spectrum and fluorescence spectrum.are achieved using crystals grown in this way. The primary outcomes are as follows:(1) The successful method synthesizing the rigorous anhydrous LiCAF and Ce:LiCAF polycrystalline material is described by the work. Using high purity fluoride as initial agents, the raw material is mixed according to stoichiometric ratio. Under the HF atmospheresafe as safe gas, the anhydrous material is obtained by sintering according to the unique fluoration technology.(2) Describing the method of growth of high performances LiCAF and Ce:LiCAF single crystals by the modified Bridgman growth under nonvacuum atmosphere. Filling the double shells platinum crucibles with the polycrystalline material, a little of polyterafluoroethylene power is added to the crucibles to exhaust the oxygen sealed in the crucibles. Growth parameters as follow: The furnace temperature is controlled at 910～930oC, the temperature gradient across solid-liquid interface is adjusted at about 30oC/cm with the lowering rate in the range of 0.5~1.0 mm/h and the furnace temperature lowering rate keeping at 20～50℃/ h. The transparent crystals are obtained from the crucibles.(3) As-grown LiCAF and Ce:LiCAF crystals are characterized by XRD, UV/VI transmission spectrum and fluorescence spectrum. The results suggest that LiCAF and Ce:LiCAF single crystals have high transparent optical properties during the UV/VI range, with Ce:LiCAF crystals have unique absorption band around the 260nm . No evident OH- absorption is observed in IRspectrum. Under the excitateding by 257 or 267nm radiation, the fluoscence spectrum of Ce:LiCAF crystals have two emission broad bands at 290nm and 310nm.(4) Descibeing the modified technology of as-grown crystals growth and processing. To improving the efficiency and reducing the cost of crystal growth, the method increasing the number of refractory tubes in the furnace or the crucibles in the refratory tube is adopted in the work. The outcomes suggest the probability of industrialization of high performances LiCAF and Ce:LiCAF single crystals. According to the analysis of characters of LiCAF and Ce:LiCAF crystals, a modified crystal processing which is same with LiCAF and Ce:LiCAF crystals is summarized.
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