Broadband conversion of visible light to near-infrared emission by Ce^3+, Yb^3+-codoped yttrium aluminum garnet

We show that Ce3+ can be an efficient sensitizer for Yb3+ in the host lattice of yttrium aluminum garnet (YAG). With blue-light excitation to induce the 4f→5d transition of Ce3+, characteristic near-IR emission of Yb3+ due to transition of 2F5/2→2F7/2 peaking at 1030 nm is generated as a result of energy transfer from Ce3+ to Yb3+. The result of spectral evolution with temperature indicates that the efficiency of energy transfer is enhanced owing to thermal effect. This evidence implies that the phonon-assisted process participates in the downconversion of YAG: Ce3+, Yb3+.