A novel photothermal process to spatially modulate the concentration of sub-wavelength, high-index nanocrystals in a multicomponent Ge-As-Pb-Se chalcogenide glass thin film resulting in an optically functional infrared grating is demonstrated. The process results in the formation of an optical nanocomposite possessing ultralow dispersion over unprecedented bandwidth. The spatially tailored index and dispersion modification enables creation of arbitrary refractive index gradients. Sub-bandgap laser exposure generates a Pb-rich amorphous phase transforming on heat treatment to high-index crystal phases. Spatially varying nanocrystal density is controlled by laser dose and is correlated to index change, yielding local index modification to ≈+0.1 in the mid-infrared.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1002/adma.201803628 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Weighted Echo State Graph Neural Networks Based on Robust and Epitaxial Film Memristors.
Adv Sci (Weinh)
January 2025
College of Physics Science & Technology, School of Life Sciences, Institute of Life Science and Green Development, Key Laboratory of Brain-Like Neuromorphic Devices and Systems of Hebei Province, Hebei University, Baoding, 071002, China.
Hardware system customized toward the demands of graph neural network learning would promote efficiency and strong temporal processing for graph-structured data. However, most amorphous/polycrystalline oxides-based memristors commonly have unstable conductance regulation due to random growth of conductive filaments. And graph neural networks based on robust and epitaxial film memristors can especially improve energy efficiency due to their high endurance and ultra-low power consumption.
View Article and Find Full Text PDFAvoided Crossing Phonons Realizes High-Performance Single-Crystalline β-ZnSb Thermoelectrics.
Adv Sci (Weinh)
December 2024
Department of Materials Science and Engineering, National Taiwan University, Taipei, 10617, Taiwan.
This study reveals the mechanisms behind the ultralow lattice thermal conductivity κ in β-ZnSb single crystals through inelastic neutron scattering (INS). Analyzing phonon behaviors and the interaction between acoustic phonons and rattling modes, the first experimental evidence of avoided crossing in β-ZnSb is provided. The rattler-phonon avoided crossings contribute to the low κ in a β-ZnSb single crystal, enhancing the thermoelectric figure-of-merit (zT).
View Article and Find Full Text PDFFast Solid-Phase Exfoliation of Layered Double Hydroxides with Tunable Functionalization.
ACS Appl Mater Interfaces
December 2024
School of Science, RMIT University, Melbourne, Victoria 3000, Australia.
Article Synopsis
- Two-dimensional layered double hydroxides (LDHs) are being explored for applications in catalysis, water treatment, and energy storage, but existing exfoliation methods face environmental and efficiency challenges.
- A new solid-phase exfoliation technique has been successfully used to create LDH nanosheets, enhancing their stability and functionality by introducing surface functional groups and defects.
- The improved LDH nanosheets, particularly NiFe-LDH, show excellent electrocatalytic performance with a low overpotential, showcasing the method's potential as a sustainable way to prepare and functionalize 2D materials.
Self-Similar Ligand for 2D Zr(IV)-Based Metal-Organic Frameworks: Fluorescent Sensing and Catalysis.
Inorg Chem
December 2024
Institute of Materials Research and Engineering (IMRE), Agency of Science, Technology and Research (A*STAR), 2 Fusionopolis Way, Singapore 138634, Republic of Singapore.
Two-dimensional (2D) metal-organic framework sheets, in comparison to the 3D analogues, offer potential advantages for intercalation of guest components between the layers, exfoliation/dispersion into solutions, and processing into thin films. As a versatile platform for leveraging organic functions, the 2D Zr(IV)-carboxylate net here features a dendritic Sierpinski tritopic linker with conjugated alkyne branches and a photoactive triphenylamine core. The 2D solid can be easily dispersed in water and many other solvents, resulting in stable and fluorescent suspension for sensing nitro aromatic compounds and Fe ions with high quenching efficiencies and ultralow limits of detection.
View Article and Find Full Text PDFUltralow Lattice Thermal Conductivity and High ZT Beyond 1 Realized in BiS Nanocomposites via Bottom-Up Structure Design.
Small
December 2024
Faculty of Materials Science and Engineering, Kunming University of Science and Technology, Kunming, 650093, China.
Bismuth sulfides (BiS), an n-type thermoelectric material, in expensive, and environmentally friendly. However, it has poor electrical conductivity due to its low electron concentration, and its thermoelectric properties need improvement. By adjusting the properties of microstructural units and then designing and preparing bulk materials, the transport properties are modulated to optimize thermoelectric properties.
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!