ErF3 microcrystals controllably deposited in perfluoride glass for upconversion red emission.

To the best of our knowledge, this paper first reports ErF3 microcrystals controllably deposited in perfluoride glass using phase-separation engineering techniques. The sample exhibited strong upconversion red-light emission owing to the small distance between Er3+ ions and low phonon energy (585 cm-1). The sample has a high red/green ratio of up to 18.6, which, to our knowledge, is the highest reported value in Er3+-doped fluoride glass ceramics. Furthermore, the sample has a long fluorescence lifetime (3.18 ms @660 nm), good color saturation (0.6255,0.3707), and good thermal stability (Δ E=0.31e V). Therefore, this sample has the potential for application across multiple fields, such as color display, visible laser, and lighting.

Broadband near-infrared luminescence in erbium ion single-doped tellurite glass for optical amplification.

This Letter proposes a simple approach for the realization of a broadband near-infrared (NIR) luminescence source in erbium ion single-doped tellurite glass, which is bent on tailoring the network structure. Under the collective action of multiple broadening mechanisms and fluorescence capture, broadband fluorescence with a full width at half maximum (FWHM) of 132 nm (1500-1632 nm) was achieved. To the best of our knowledge, this is the largest FWHM reported for erbium single-doping of tellurite glass materials. Meanwhile, this fiberglass exhibits excellent thermal stability and high visible to NIR transmittance. Furthermore, a novel equivalent five-level Stark splitting model is proposed that can effectively explain the spectrum broadening. This study is beneficial for the further development of broadband optical amplification.

Perfluoride glass ceramic transmitting from UV to far-IR tailored by one step.

This Letter highlights a cost-effective, simple, and rapid one-step process leading to the (Sr0.84Lu0.16) F2.16 glass ceramic in a completely new perfluoride system. The mechanism was demonstrated clearly. This material shows high transparency in the UV (0.35 µm) range up to far-IR (10.8 µm). In addition, low phonon energy, as well as good mechanical properties, chemical durability, spectral performance, and long lifetime (7.2 ms) of Er3+:2.7 µm are also possessed by this material. This Letter effectively breaks through the performance limitation of a glass matrix on fluoride crystallites in glass ceramics for the first time, to the best of our knowledge. Meanwhile, it also provides a promising optical material for windows and lasers by a simple and cheap method.

Er(3+)-doped transparent glass ceramics containing micron-sized SrF2 crystals for 2.7 µm emissions.

Er(3+)-doped transparent glass ceramics containing micron-sized SrF2 crystals were obtained by direct liquid-phase sintering of a mixture of SrF2 powders and precursor glass powders at 820 °C for 15 min. The appearance and microstructural evolution of the SrF2 crystals in the resulting glass ceramics were investigated using X-ray diffraction, field-emission scanning electron microscopy and transmission microscopy. The SrF2 crystals are ~15 µm in size and are uniformly distributed throughout the fluorophosphate glass matrix. The glass ceramics achieve an average transmittance of 75% in the visible region and more than 85% in the near-IR region. The high transmittance of the glass ceramics results from matching the refractive index of the SrF2 with that of the precursor glass. Energy dispersive spectroscopy, photoluminescence spectra, and photoluminescence lifetimes verified the incorporation of Er(3+) into the micron-sized SrF2 crystals. Intense 2.7 µm emissions due to the (4)I11/2 → (4)I13/2 transition were observed upon excitation at 980 nm using a laser diode. The maximum value of the emission cross section of Er(3+) around 2.7 µm is more than 1.2 × 10(-20) cm(2), which indicates the potential of using transparent glass ceramics containing micron-sized SrF2 crystals for efficient 2.7 µm lasers and amplifiers.