Temperature-mediated appearance and disappearance of a deflection grating in a diffracting structure is possible by employing InSb as the grating material. InSb transits from the dielectric state to the plasmonic state in the terahertz regime as the temperature increases, this transition being reversible. An intermediate state is the vacuum state in which the real part of the relative permittivity of InSb equals unity while the imaginary part is much smaller. Then the grating virtually disappears, deflection being impossible as only specular reflection can occur. This ON/OFF switching of deflection and relevant angular filtering are realizable over wide ranges of frequency and incidence angle by a temperature change of as low as 20 K. The vacuum state of InSb invoked for ON/OFF switching of deflection and relevant angular filtering can also be obtained for thermally tunable materials other than InSb as well as by using non-thermal mechanisms.
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http://dx.doi.org/10.1038/s41598-018-32977-z | DOI Listing |
ACS Nano
January 2025
School of Materials Science and Engineering, Peking University, Beijing 100871, People's Republic of China.
Single-crystal Au(111), renowned for its chemically inert surface, long-range "herringbone" reconstruction, and high electrical conductivity, has long served as an exemplary template in diverse fields, , crystal epitaxy, electronics, and electrocatalysis. However, commercial Au(111) products are high-priced and limited to centimeter sizes, largely restricting their broad applications. Herein, a low-cost, high-reproducible method is developed to produce 4 in.
View Article and Find Full Text PDFAdv Sci (Weinh)
January 2025
Institute for Superconducting & Electronic Materials (ISEM), Faculty of Engineering and Information Sciences (EIS), University of Wollongong, Wollongong, NSW, 2500, Australia.
Rechargeable batteries are central to modern energy storage systems, from portable electronics to electric vehicles. The cathode material, a critical component, largely dictates a battery's energy density, capacity, and overall performance. This review focuses on the application of operando X-ray absorption spectroscopy (XAS) to study cathode materials in Li-ion, Na-ion, Li-S, and Na-S batteries.
View Article and Find Full Text PDFJ Cataract Refract Surg
January 2025
The John Moran Eye Center, Department of Ophthalmology, University of Utah, Salt Lake City, Utah.
Purpose: To compare the efficiency of peristaltic vs venturi vacuum platforms when applied to the femtosecond treated cataract.
Setting: Outpatient Eye Center, Mercy Health System, Springfield, MO, USA.
Design: This is a prospective randomized controlled trial of 111 patients with moderate nuclear sclerosis scheduled for bilateral routine laser cataract surgery (clinicaltrials.
Nanomaterials (Basel)
January 2025
State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China.
Copper matrix composites (CMCs) synergistically reinforced with rare earth oxides (ReO) and TiC were prepared using a powder metallurgy process with vacuum hot-pressing and sintering technology, aiming to explore new ways to optimize the properties of composites. Through this innovative approach, we propose a new solution strategy and idea for the difficult problem of mutual constraints between electrical and mechanical properties faced by traditional dual-phase reinforced Cu-matrix composites. Meanwhile, the modulation mechanism of ReO in CMCs and the electrical and mechanical properties of the composites were investigated.
View Article and Find Full Text PDFNanomaterials (Basel)
January 2025
Department of Physics and Astronomy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-3255, USA.
In this study, a single zirconium carbide (ZrC) nanoneedle structure oriented in the <100> direction was fabricated by a dual-beam focused ion beam (FIB-SEM) system, and its field emission characteristics and emission current stability were evaluated. Benefiting from controlled fabrication with real-time observation, the ZrC nanoneedle has a smooth surface and a tip with a radius of curvature smaller than 20 nm and a length greater than 2 μm. Due to its low work function and well-controlled morphology, the ZrC nanoneedle emitter, positioned in a high-vacuum chamber, was able to generate a single and collimated electron beam with a current of 1.
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