Bi-Yb co-doped ultra-broadband luminescent silica glass based on glass phase separation technology

Broad-spectrum light sources are widely used in optical fiber sensing and spectral analysis. At present, the supercontinuum spectrum generated by photonic crystal fiber nonlinearity covers a wide range of wavelengths, while it is a challenge to make the spectral flat, especially in 1000-1200nm range. In comparison, ultra-broadband light sources generated by doped fibers have better flatness. Bi-doped glass and optical fibers have attracted much attention in the field of ultra-broadband light sources and optical amplifiers due to their ultra-broadband spontaneous emission. We prepared Bi-doped quartz glass by glass phase separation method, and synthesized Bi active center-Al (BAC-Al) in glass by controlling the valence state of Bi by sintering atmosphere, which possess luminescence at 1120nm. Yb and Bi were simultaneously incorporated into glass for achieving combined BAC-Al and Yb luminescence. The combined spectrum covers 1000-1250nm, and the half maximum full width can reach 150nm. Various properties of the glass are tested, and the luminescence of bismuth and ytterbium in the glass are studied. The energy transfer between Bi and Yb was discovered, which can help to infer the energy level of BAC-Al. This work not only provides new materials and methods for ultra-broadband light sources, but also provides new ideas for exploring the near-infrared luminescence principle of Bi.