Structural, spectroscopic and thermal properties of hot-pressed Nd:(Ca0.94Gd0.06)F2.06 transparent ceramics

0.5-5.0 at.% Nd3+ doped (Ca0.94Gd0.06)F2.06 transparent ceramics were fabricated by vacuum hot-pressing sintering. The structural, spectroscopic and thermal properties of Nd:(Ca0.94Gd0.06)F2.06 transparent ceramics, as well as the influence of Nd3+ content on these properties were investigated. The as-fabricated ceramic samples exhibited high transparency and nearly pore-free microstructure. The absorption peaks located at 538 nm, 576 nm, 736 nm, 792 nm and 865 nm were attributed to the transitions from ground state to the excited states of Nd3+ ions, and the absorption coefficients increased linearly with Nd3+ content increasing. The emission band of the sample doped with 1 at.% Nd3+ concentration exhibited the highest emission intensity, while the lifetime decreased sharply with the increase of Nd3+ concentration. In addition, with Nd3+ content increasing from 0.5 to 5.0 at.%, the thermal expansivity coefficients increased slightly, while the thermal conductivity decreased from 4.21 to 2.36 W/m K at room temperature.