Robust YAG:Ce single crystal for ultra-high efficiency laser lighting

At present,solid-state laser-driven lighting fabricated with blue laser diode(LD)and phosphor has been greatly developed in high-power lighting applications.The major obstacle is the luminescence saturation threshold of the fluorescence conversion material(YAG:Ce).In this work,we successfully prepared a series of high-quality and robust YAG:Ce single crystals.With high quantum efficiency(QE=92%),regular crystal structure and high thermal conductivity,the single-crystal has excellent ability to deal with high radiation flux and thermal accumulation generated by high power.Matching the single-crystal with the laser,the luminous efficiency up to 274 lm/W and saturation threshold of 12 W/mm^(2) were obtained.In addition,the influence of Ce doping concentration and sample processing conditions on the indicators in laser-driven white lighting was systematically studied.The results are of great significance and are believed to promote the development of solid-state laser-driven lighting.