Fig. 3: High-angle annular dark-field transmission (HAADF) TEM micrograph of 0.35 at.% Nd:Al2O3 bulk ceramic (optimized sample) with corresponding energy-dispersive X-ray spectroscopy (EDS) elemental maps for Al, O, and Nd (L-Lines).

The EDS maps reveal that a significant portion of the Nd dopant is found within the matrix. In addition, there is some Nd along some grain boundaries and triple points