Fig. 4

Mechanical and optical properties of the YAG-Al₂O₃ nanoceramic. a Typical load-displacement curves of the AY26 ceramic synthesized at 1100 °C and compared to commercial micrometer scale YAG transparent ceramic and YAG single crystal. The indentation morphology of the AY26 ceramic is embedded. b Photoluminescence excitation and emission spectra of the Ce³⁺-doped YAG-Al₂O₃ ceramic. The dotted line is the excitation spectrum; the red and green lines are the photoluminescence emission spectra under excitation at 460 and 340 nm, respectively. The photograph of the ceramic sample recorded under 460 nm laser excitation (4 mW power) and its energy levels diagram are embedded. c Color coordinates of the YAG-Al₂O₃ ceramic under 460 nm LED excitation for various thicknesses (from 0.5 to 1.1 mm) and Ce³⁺ doping contents (from 0.1 at% to 2 at%). The curved line corresponds to the Planckian black-body locus. d Photograph of the YAG-Al₂O₃ ceramic-based WLED under a driving current of 60 mA. The photograph of the ceramic sample (0.1 at% Ce³⁺) is embedded