Excellent luminous efficiency and high thermal stability of glass-in-LuAG ceramic for laser-diode-pumped green-emitting phosphor

Abstract

A kind of glass-in-LuAG (GIP) ceramic with excellent luminous efficiency and high thermal stability was fabricated by solid-state sintering for laser diode (LD)-pumped green-emitting phosphor. The GIP ceramic employing particularly designed borosilicate glass as adhesive exhibits high thermal conductivity (2.8 W/m·K at 80°C) and remarkable improvement in thermal stability (T_g=711°C) and reliability (luminous flux has only a 0.5% drop after 100 h at 300°C). When the GIP ceramic is pumped by 455 nm blue LDs (14.5 W/mm²), a luminous efficacy of 205 lm/W was achieved. More importantly, the GIP ceramic did not have luminescence saturation even under a higher power density (17.1 W/mm²) excitation. The novel GIP ceramic, possessing good optical and thermal properties, is promising for LD-pumped green-emitting phosphor.