Optical Properties of Ce~(3+) doped (LuGd)_2CaMg_2Si_3O_(12) Yellow phosphors

Yttrium aluminum garnet structure of yellow-phosphors(LuM)2CaMg2Si3O12∶ Ce3 +varying Gd concentrations(1 ~ 5mol%)were synthesized by the high temperature solid-state method. Crystalline phase was investigated by powder XRD. The results revealed the second phases began to grow in doped Ce3 +samples. However,phase structure remained unchanged when Gd was introduced into the samples.Optical properties of the samples were characterized by application of photoluminescence spectroscopy. The variation of PL and PLE spectra were studied as a function of Ce concentration as well as Gd content. The emission intensity increased with the Ce3 +concentration up to 2 at%and then decreased and the emission peak position shifted to a longer wavelength slightly. However,the emission peak position continuously shifted from 561nm at 1at% of Gd3 +to 568nm as the Gd3 +content increased to 5at%,and emission intensity decreased significantly. The phosphors can be efficiently excited by the incident light of 465nm,well matched with the emission band of 465nm-emitting InGaN chip,and emission wavelength was longer than that of YAG ∶ Ce3 +,So the phosphors is a promising candidate to complement YAG color rendering index in blue-LEDs + YAG ∶ Ce3 +white light systems.