Erbium-doped Ce:YAG phosphor begets bright 1540 nm emission

An efficient energy transfer from cerium ions (Ce³⁺) to erbium ions (Er³⁺) in a yttrium aluminum garnet (YAG) matrix has enabled a new class of material that could be an efficient near-infrared emitter, say scientists at Hong Kong Baptist University (Hong Kong) and Jinan University (Guangzhou, China). The transfer from Ce³⁺ toEr³⁺ in erbium-doped Ce:YAG emission generates a 1000-fold increase in Er³⁺ emission at 1540 nm. Previous studies of Er³⁺ have shown that emission at 1540 nm is usually weak partly due to the 4f forbidden transition. Fluorescence of Ce³⁺, with an allowed d-f transition, is more efficient, transferring to the erbium ions via the matched energy level ⁴F_9/2.

The researchers used a 476 nm argon laser to achieve photoluminescence of the Ce,Er:YAG phosphor, and a xenon-lamp monochromator setup to measure the excitation. Typical dispersed light power at 470 nm was 20 to 70 µW. The 1540 nm emission could be easily achieved via illumination from a simple gallium nitride light-emitting diode, which means it could hold great promise for use in fiber-optic communications. Contact Jian Xin Meng at [email protected].