New fabrication process of anisotropic laser ceramics
Transparent polycrystalline media are expected to provide the next generation lasers due to their capability for engineered structure and productivity of large volume media that brings power scalability of high power laser oscillators [1]. However, conventional laser ceramics were limited to cubic materials, since optical scattering at randomly oriented grain boundaries should be occurred if materials have anisotropic crystallographic nature. The grain orientation techniques of anisotropic ceramics have been investigated using various methods, though it is difficult to obtain a large and homogeneously oriented transparent material. Actually, there is no report of anisotropic materials such as transparent YVO4 ceramics and FAP ceramics in our knowledge. In this research, a new method of “advanced electromagnetic processing” has been established for fabricating transparent rare-earth doped anisotropic ceramics toward the Giant Micro Photonics [2]. We applied it for RE:FAP (RE:Ca10(PO4)6F2) materials that have excellent optical properties such as high absorption efficiency, high emission cross-section and long lifetime.