Used in phosphor materials for display technologies, including cathode ray tubes and LED-based lighting, due to its luminescent properties when doped with rare earth elements. Employed in the production of infrared-transmitting glasses and optical coatings, where it enhances performance in the near-infrared spectrum. Serves as a semiconductor material in specialized electronic applications, particularly in thin-film form for optoelectronic devices. Investigated for use in solid-state lasers and scintillation detectors owing to its ability to host activator ions and emit light under radiation. Also explored in nanotechnology for developing bioimaging agents and targeted therapeutic systems.