Synthesis and Characterization of Li₂MgGeO₄:Ho³

In this work, the synthesis and characterization of Li₂MgGeO₄:Ho³⁺ ceramics were reported. The X-ray diffraction measurements revealed that the studied ceramics belong to the monoclinic Li₂MgGeO₄. Luminescence properties were analyzed in the visible spectral range. Green and red emission bands correspondent to the ⁵F₄,⁵S₂→⁵I₈ and ⁵F₅→⁵I₈ transitions of Ho³⁺ were observed, and their intensities were significantly dependent on activator concentration. Luminescence spectra were also measured under direct excitation of holmium ions or ceramic matrix. Holmium ions were inserted in crystal lattice Li₂MgGeO₄, giving broad blue emission and characteristic 4f-4f luminescent transitions of rare earths under the selective excitation of the ceramic matrix. The presence of the energy transfer process between the host lattice and Ho³⁺ ions was suggested.