Investigation of an LuAG:Ce translucent ceramic synthesized via spark plasma sintering: Towards a facile synthetic route, robust thermal performance, and high-power solid state laser lighting

The aim of this study is to investigate a thermally robust green-yellow color converter for high-power solid state laser lighting applications. LuAG:Ce translucent ceramics (TCs) were synthesized via the spark plasma sintering (SPS) technique and LiF was used as additive. The as-prepared ceramics show remarkably superior thermal and luminescent properties: a high external quantum efficiency (77%), a low thermal quenching (4.1% drop at 200 °C), a good thermal conductivity (6.3 W m−1K−1), and a high reliability (only a 1.9% drop after 1000 h, at 85 °C and 85% humidity). A prototype lamp using the TC (and a 450 nm laser diode), with the increasing driving power (up to 8.7 W), shows increasing luminous flux (238-472 lm) with stable luminous efficiency (54.3-56.6 lm/W). This indicates that the translucent ceramic can be used for high-power laser-lighting.