Enhanced the yellow emission of Dy³⁺/Eu³⁺: Na₅Lu₉F₃₂ fluoride single crystals by the introduction of inactive central Y³⁺ ions

High-quality Na5Lu9F32 single crystals incorporated with Dy3+, Dy3+/Eu3+, and Dy3+/Eu3+/Y3+ ions were successfully synthesized by a reformative Bridgman technique. A significantly enhanced 573nm yellow emission for the Dy3+/Eu3+ incorporated crystal by dopant of inactive central Y3+ ions was demonstrated upon excitation of 453nm. The broken of the Dy3+ clusters by addition of Y3+ dopant was probably the main reason for the enhancement of the yellow emission. The crystal still held the phase of Na5Lu9F32 although the doping level reaches to 1.5 mol% Y3+ while the peaks of X-ray diffraction (XRD) were slightly blue-shifted, and Y3+ ions replaced the Lu3+ lattices as consequence of Rietveld structure refinements of the crystals. The maximum excited absorption and emission cross-sections at 573nm were also computed to be similar to 8.91x10(-21) and similar to 6.06x10(-21) cm(2) separately. Therefore, the Dy3+/Eu3+/Y3+ tri-doped Na5Lu9F32 single crystal was considered as a prospective yellow solid-state laser material for related optical devices.