Cooperative luminescence phenomenon of Yb:YAG crystals was studied. Up-converted blue luminescence was obviously observed in Yb:YAG under excitation in the near-infrared region with a wavelength 940 nm. Experimental evidence was provided by the fact that the intensity of 498 nm luminescence shows a quadratic dependence on excitation power, and the intensity of blue luminescence increased with the increase in Yb ion concentration. It is concluded that this luminescence is due to a cooperative process resulting from a strong interaction of Yb ions. The cooperative luminescence is possiblely assigned to the strong interaction of 4f(13) electrons and neighboring Yb3+ ions in a covalent host lattice such as YAG. Theoretical cooperative luminescence spectrum was calculated.
Download full-text PDF |
Source |
|---|
Publication Analysis
Top Keywords
Similar Publications
Stretchable Thermochromic Fluorescent Fibers Based on Self-Crystallinity Phase Change for Smart Wearable Displays.
Polymers (Basel)
December 2024
Engineering Research Center of Technical Textiles, Ministry of Education, College of Textiles, Donghua University, Shanghai 201620, China.
Smart fibers with tunable luminescence properties, as a new form of visual output, present the potential to revolutionize personal living habits in the future and are receiving more and more attention. However, a huge challenge of smart fibers as wearable materials is their stretching capability for seamless integration with the human body. Herein, stretchable thermochromic fluorescent fibers are prepared based on self-crystallinity phase change, using elastic polyurethane (PU) as the fiber matrix, to meet the dynamic requirements of the human body.
View Article and Find Full Text PDFApplication of Solution-Processed High-Entropy Metal Oxide Dielectric Layers with High Dielectric Constant and Wide Bandgap in Thin-Film Transistors.
Micromachines (Basel)
November 2024
Southwest Institute of Technology and Engineering, Chongqing 400039, China.
High-k metal oxides are gradually replacing the traditional SiO dielectric layer in the new generation of electronic devices. In this paper, we report the production of five-element high entropy metal oxides (HEMOs) dielectric films by solution method and analyzed the role of each metal oxide in the system by characterizing the film properties. On this basis, we found optimal combination of (AlGaTiYZr)O with the best dielectric properties, exhibiting a low leakage current of 1.
View Article and Find Full Text PDFMeasuring plant cysteine oxidase interactions with substrates using intrinsic tryptophan fluorescence.
Sci Rep
December 2024
Department of Biology, University of Oxford, Oxford, OX1 3RB, UK.
Plant Cysteine Oxidases (PCOs) are oxygen-sensing enyzmes that catalyse oxidation of cysteinyl residues at the N-termini of target proteins, triggering their degradation via the N-degron pathway. PCO oxygen sensitivity means that in low oxygen conditions (hypoxia), their activity reduces and target proteins are stabilised. PCO substrates include Group VII Ethylene Response Factors (ERFVIIs) involved in adaptive responses to the acute hypoxia experienced upon plant submergence, as well as Little Zipper 2 (ZPR2) and Vernalisation 2 (VRN2) which are involved in developmental processes in hypoxic niches.
View Article and Find Full Text PDFSingle-phase dye-embedded triple-emitting EY&BPEA@Zr-MOFs for selective detection of inorganic ions in environmental water.
Spectrochim Acta A Mol Biomol Spectrosc
December 2024
School of Applied Chemistry and Materials, Zhuhai College of Science and Technology, No. 8 Anji East Road, Zhuhai 519040, China. Electronic address:
The synthesis of multi-wavelength emission fluorescent metal-organic framework sensors has received widespread attention in recent years. Under solvothermal conditions, a series of triple-emission fluorescent sensors were fabricated by in situ encapsulation of red emitting Eosin Y and green emitting 9,10-bis(phenylethynyl)anthracene (BPEA) into a blue emitting naphthalene-based Zr-MOF. By combining the dye quantity regulation and the resonance energy transfer between MOFs and dyes, the single-phase EY&BPEA@Zr-MOFs exhibited tunable triple-emission fluorescence.
View Article and Find Full Text PDFExcited-State Engineering of Chalcogen-Bridged Chiral Molecules for Efficient OLEDs with Diverse Luminescence Mechanisms.
Angew Chem Int Ed Engl
December 2024
Guangdong Basic Research Center of Excellence for Energy and Information Polymer Materials, State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Wushan Road 381, Tianhe District, Guangzhou, 510640, Guangdong Province, P. R. China.
The exploration of circularly polarized luminescence is important for advancing display and lighting technologies. Herein, by utilizing isomeric molecular engineering, a novel series of chiral molecules are designed to exploit both thermally activated delayed fluorescence (TADF) and room-temperature phosphorescence (RTP) mechanisms for efficient luminescence. The cooperation of a small singlet-triplet energy gap, moderate spin-orbital coupling (SOC), and large oscillator strength enables efficient TADF emission, with photoluminescence quantum yields exceeding 90 %.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!