Phys.org October 18, 2023 A widely tunable and high resolution mid-infrared radiation source operating in the 3–5 µm region has been applied to numerous frontier applications. However, due to the narrow absorption peak linewidth of atmospheric molecules, it is necessary to strictly align the output wavelength with the target wavelength, which requires high wavelength resolution. Researchers in China tuned the temperature and angle of BaGa4Se7 (BGSe) crystals simultaneously placing the crystals in a temperature-controlled furnace, and placed the furnace on an electric rotary platform. This scheme achieved both wide-range wavelength tuning and high-resolution wavelength tuning with stable output wavelength. It […]
Working towards programmable matter: Unexpected behavior discovered in active particles
Phys.org October 23, 2023 In theoretical models for active particles, it is often assumed that the particles’ swimming speed is always the same. However, this is not so for particles produced in many experiments. An international team of researchers (UK, Germany) used a combination of computer simulations and theoretical derivations, to study the behavior of systems consisting of many active particles whose speed depended on orientation. In the process they discovered a series of new effects. They found that systems consisting of many active particles could spontaneously form clusters—even when the individual particles do not attract one another. The particles […]
Top 10 Science and Technology Inventions for the Week of October 20, 2023
01. Move over carbon, the nanotube family just got bigger 02. New catalyst could provide liquid hydrogen fuel of the future 03. Novel approach to advanced electronics, data storage with ferroelectricity 04. Photonic crystals bend light as though It were under the influence of gravity 05. Physicists create new form of antenna for radio waves 06. Researchers test seafloor fiber optic cable as an earthquake early warning system 07. Solving quantum mysteries: New insights into 2D semiconductor physics 08. Study hints at new way to improve on spintronics for future tech 09. Superlensing without a super lens: Physicists boost microscopes […]
New catalyst could provide liquid hydrogen fuel of the future
Science Daily October 12, 2023 Hydrogen for energy storage and hydrogen-powered fuel cells for energy conversion can play important roles. However, storage of hydrogen itself is difficult. Researchers in Sweden investigated a car fuel comprised of a liquid that is converted to hydrogen by a solid catalyst. The used liquid is then emptied from the tank and charged with hydrogen, after which it can be used again. A key part in the adaption of liquid organic hydrogen carriers (LOHCs) is the catalyst design for efficient dehydrogenation of these hydrogen-carrying species. They investigated the use of silica- and alumina-supported POCOP–Ir systems […]
Accelerating Interoperability Standards for Commercial Lunar Infrastructure
DARPA October 11, 2023 Many shareable, scalable commercial systems will be needed to support a future lunar ecosystem. Through the Lunar Guidelines for Infrastructure Consortium (LOGIC) logic.jhuapl.edu/ . , DARPA will convene stakeholders across industry, academia, and government to identify critical lunar infrastructure interoperability and interface needs. The Johns Hopkins University (JHU) Applied Physics Laboratory (APL) will administer LOGIC, providing technical leadership and management of the consortium. LOGIC envisions a permanent, self-sustaining, and independent forum where international industry, government and academia can collaborate for the benefit of the entire lunar community. LOGIC will foster international engagement and the required technical […]
AI just got 100-fold more energy efficient
Science Daily October 12, 2023 Although support vector machine algorithms for electrocardiogram classification show high classification accuracy, hardware implementations for edge applications are impractical due to the complexity and substantial power consumption needed for kernel optimization when using conventional CMOS circuits. A team of researchers in the US (Northwestern University, University of Southern California) has shown that reconfigurable mixed-kernel transistors based on dual-gated van der Waals heterojunctions could generate fully tunable individual and mixed Gaussian and sigmoid functions for analogue support vector machine kernel applications. The heterojunction-generated kernels can be used for arrhythmia detection from electrocardiogram signals with high classification […]
Move over carbon, the nanotube family just got bigger
Phys.org October 16, 2023 Single-walled TMD nanotubes (SW-TMDNTs) are 1D materials that can exhibit tunable electronic properties depending on both their chirality and composition. However, much less has been explored about their geometrical structures and chemical variations due to their instability under ambient conditions. Researchers in Japan have shown that the outer surfaces and inner cavities of the BNNTs promote and stabilize the coaxial growth of SW-TMDNTs with various diameters, including few-nanometers-wide species. The chiral indices of individual SW-MoS2NTs were assigned by high-resolution transmission electron microscopy, and statistical analyses revealed a broad chirality distribution ranging from zigzag to armchair configurations. […]
New study reveals the influence of natural climate drivers on extreme monsoons in Pakistan
Phys.org October 13, 2023 Given this region’s long history of floods and droughts, the role of natural climate variability cannot be rejected without a careful diagnosis. An international team of researchers (USA – Oak Ridge National Laboratory, Princeton, Stanford, University of Tennessee, Washington State University, Northeastern University, Pacific Northwest National Laboratory, Tufts University, Italy, India) examined how oceanic and atmospheric variability has contributed to unusual precipitation distributions in West South Asia. Variations in sea surface temperatures in the tropical Pacific and northern Arabian Sea, and internal atmospheric variability related to the circumglobal teleconnection pattern and the subtropical westerly jet stream, […]
Novel approach to advanced electronics, data storage with ferroelectricity
Phys.org October 16, 2023 Ferroelectrics possess a spontaneous polarization that is switchable by an electric field and is critical for the development of low energy nanoelectronics and neuromorphic applications. However, the realization of switchable polarization in metal oxides with simpler structures has been a major challenge. An international team of researchers (Australia, India) demonstrated the presence of robust switchable polarization at the level of a single nanocrystalline in magnesium-doped zinc oxide thin films with polar wurtzite crystal structures. Voltage control of the polarization and the coupled electronic transport behavior revealed a giant resistance change of approximately 10000% . Time- and […]
Photonic crystals bend light as though It were under the influence of gravity
Nanowerk October 16, 2023 An international team of researchers (Japan, Spain) demonstrated electromagnetic waves following a gravitational field using a photonic crystal. They introduced spatially distorted photonic crystals (DPCs) capable of deflecting light waves owing to their pseudo gravity caused by lattice distortion. They experimentally verified the phenomenon in the terahertz range using a silicon DPC. Pseudo gravity caused by lattice distortion revealed alternative approaches to achieve on-chip trajectory control of light propagation in PCs. Their work has far-reaching implications for the world of optics and materials science, and bear significance for the development of 6G communications… read more. TECHNICAL […]