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At present, the market of compact visible light sources (both coherent and incoherent) is dominated by wide-bandgap semiconductor devices. While the modern electroluminescent diodes (LEDs) allow obtaining the full palette of colors of visible light, the semiconductor laser diodes (LDs) cover this range only partially, enabling lasing in 400-488 nm, 510-520 nm, and 630-690 nm and leaving the remaining part of the visible spectrum not addressed. The missing wavelengths are to some extent complemented by DPSSLs with frequency conversion but suffer from lower efficiency and more complex design. The remaining spectral gaps are continuously the subject of intensive research and development works, which cover the investigation of a new light-emitting media, both semiconductors, and solid-state materials. Among these, dysprosium-doped glasses are of specific interest due to the unique possibility of obtaining yellow emission and lasing, hardly available to any other laser sources, specifically when compact design, high output power, and good beam quality are of concern. Additionally, the favorable energy scheme of this ion allows excitation with wide-bandgap InGaN/GaN semiconductor diodes emitting in the violet-blue range.
In this work, we summarize the results of investigation and analysis of the luminescent properties in the visible, and specifically yellow part of the spectrum, of a set of optically active glasses doped with dysprosium ions. The investigated materials cover fluoride (ZBLAN), telluride (TZN), and silica glasses, as well as composite materials based on polymer matrices doped with active nanocrystals. The research was focused on a detailed analysis of major spectroscopic features – absorption, emission, and excitation spectra, fluorescence kinetics, pumping schemes, and deexcitation processes, followed by the analysis of potential lasing properties of investigated materials.
ACKNOWLEDGMENT: The research presented here has been supported by the FOTECH-1 project granted by Warsaw University of Technology under the program Excellence Initiative: Research University (ID-UB).
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