Focused ion beams are used to pattern GaAs(001) surfaces with an array of nanometer-deep holes upon which deposition of InAs results in quantum dot formation at the hole location. Experiments show that the size and quantity of quantum dots formed depend on growth parameters, and ion dose, which affects the size and shape of the resulting holes. Quantum dots fabricated in this fashion have a photoluminescence peak at 1.28 eV at 77 K, indicating that the ion irradiation due to patterning does not destroy their optical activity. Kinetic Monte Carlo simulations that include elastic relaxation qualitatively model the growth of dots in nanometer-deep holes, and demonstrate that growth temperature, depth of the holes, and the angle of the hole sidewalls strongly influence the number of quantum dots that form at their perimeter.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1088/0957-4484/20/28/285305 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Ultrasensitive point-of-care multiplex diagnosis for influenza virus based robust quantum dot microsphere-lateral flow immunoassay.
Biosens Bioelectron
January 2025
Key Lab for Special Functional Materials of Ministry of Education, and School of Nanoscience and Materials Engineering, Henan University, 475004, Kaifeng, China. Electronic address:
Influenza A virus (IAV) and influenza B virus (IBV) with similar symptoms of infection caused a serious disease burden and economic losses in annual epidemic season, so it is important to quickly and accurately detect and distinguish between IAV and IBV during influenza season. Herein, the quantum dot microspheres (QDMS) were synthesized and applied to lateral flow immunoassays (LFIA), and a point-of-care (POC) biosensor that can discriminately and simultaneously diagnose IAV and IBV within 10 min was established. A double-sandwich QDMS nanotags was synthesized by immobilizing hydrophobic quantum dots (QDs) with chemical bonding method on a silica sphere template with an outer silica shell protection showed excellent stability and high fluorescence.
View Article and Find Full Text PDFPhotochromic Color Tuning of Copper-doped Zinc Sulfide Nanocrystals by Control of Local Dopant Environments.
Angew Chem Int Ed Engl
January 2025
Ritsumeikan University: Ritsumeikan Daigaku, Applied Chemistry, B805 Biolink, 1-1-1 Nojihigashi, 525-8577, Kusatsu, JAPAN.
Inorganic photochromic materials offer several advantages over organic compounds, including relatively inexpensive and higher thermal stability. However, tuning their color with the same component has remained a significant challenge. In this study, we demonstrate that the photochromic color of Cu-doped ZnS nanocrystals (NCs), which is initially pale yellow before light irradiation, can be tuned from gray to brown by adjusting the surface stoichiometry of Zn and S, which is controlled through the use of thiol and non-thiol ligands.
View Article and Find Full Text PDFExploring Surface State and Exciplex Dominated Aggregation Induced Electrochemiluminescence of Graphene Quantum Dots Prepared Via Electrochemical Exfoliation.
Chemphyschem
January 2025
Western University, Chemistry, 1151 Richmond St, N6A5B7, London, CANADA.
Graphene quantum dots (GQDs) have emerged as promising materials for electrochemiluminescence (ECL) applications due to their unique optical and electronic properties. In this study, GQDs were synthesized via electrochemical exfoliation of graphite in a constant current density mode, enabling scalable production with controlled size and surface functionalization. GQDs-4 and GQDs-20, synthesized at applied current densities of 4 mA/cm2 and 20 mA/cm2 to the graphite electrode, respectively, were investigated on roles of surface states and exciplex dominated aggregation-induced emission (AIE) in their ECL performance.
View Article and Find Full Text PDFRealizing zero-threshold population inversion plasmonic doping.
Nanoscale
January 2025
Key Laboratory of 3D Micro/Nano Fabrication and Characterization of Zhejiang Province, School of Engineering, Westlake University, 18 Shilongshan Road, Hangzhou 310024, Zhejiang Province, China.
Lowering the population inversion threshold is key to leveraging quantum dots (QDs) for nanoscale lasing and laser miniaturization. However, optical realization of population inversion in QDs has an inherent limitation: the number of excited electrons per QD is bound by the absorbed photons. Here we show that one can break this population limit and realize near-zero threshold inversion plasmonic doping.
View Article and Find Full Text PDFEnhanced Homogeneous Photocatalytic Hydrogen Evolution in a Binuclear Bio-inspired Ni-Ni Complex Bearing Phenanthroline and Sulfidophenolate Ligands.
Chemistry
January 2025
National & Kapodistrian University of Athens, Chemistry, Panepistimiopolis, Zografou, 15771, Athens, GREECE.
The prominence of binuclear catalysts underlines the need for the design and development of diverse bifunctional ligand frameworks that exhibit tunable electronic and structural properties. Such strategies enable metal-metal and ligand-metal cooperation towards catalytic applications, improve catalytic activity, and are essential for advancing multi-electron transfers for catalytic application. Hereby, we present the synthesis, crystal structure, and photocatalytic properties of a binuclear Ni(II) complex, [Ni2(1,10-phenanthroline)2(2-sulfidophenolate)2] (1), which crystallizes in the centrosymmetric triclinic system (P-1) showing extensive intra- and inter- non-coordinated interactions.
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!