Fluoride Transparent Ceramics

Yb3+ doped CaF2 single crystal has demonstrated high efficiency for broadband tunable laser emission or short pulse duration generation, especially at low temperature [1-4]. The challenge is now to reach a high enough quality level of transparent ceramics of this compound to compete with these single crystals. We are preparing and studying this compound [5-7] in the ceramic form. In this paper, we will describe the entire preparation process by a conventional ceramic route from the synthesis of the powders to the sintering treatment leading to a transparent material. The samples have been characterized during each step of the preparation process. The origin of the residual light scattering sources has been studied in order to be reduced even if their level is low enough to allow laser effect. A spectroscopic study allows comparing the Yb3+ sites in our ceramics and in single crystals.