Phys.org March 14, 2024 MXenes are a family of 2D materials typically formed by etching the A element from a parent MAX phase. Computational screening for other 3D precursors suitable for such exfoliation is challenging because of the intricate chemical processes involved. Researchers in Sweden proposed a theoretical approach for predicting 2D materials formed through chemical exfoliation under acidic conditions by identifying 3D materials amenable for selective etching. From a dataset of 66,643 3D materials, they identified 119 potentially exfoliable candidates, within several materials families. To corroborate the method, they chose a material distinctly different from MAX phases, in terms […]
Tag Archives: S&T Sweden
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 […]
Cutting edge transistors for semiconductors of the future
Science Daily July 3, 2023 Researchers in Sweden have demonstrated the integration of a ferroelectric gate stack on a heterostructure tunnel field-effect transistor (TFET) with subthermionic operation. Based on the ultrashort effective channel created by the band-to-band tunneling process, the localized potential variations induced by single domains and individual defects were sensed without physical gate-length scaling required for conventional transistors. They electrically measured abrupt threshold voltage shifts and quantified the appearance of new individual defects activated by the ferroelectric switching. According to the researchers their results show that ferroelectric films can be integrated on heterostructure devices and indicated that the […]
Breakthrough in magnetic quantum material paves way for ultra-fast sustainable computers
Nanowerk April 13, 2023 The discovery of van der Waals (vdW) magnets opened a new paradigm for condensed matter physics and spintronic technologies. However, the operations of active spintronic devices with vdW ferromagnets are limited to cryogenic temperatures, inhibiting their broader practical applications. Researchers in Sweden have demonstrated robust room-temperature operation of lateral spin-valve devices using the vdW itinerant ferromagnet Fe5GeTe2 in heterostructures with graphene. They measured room-temperature spintronic properties of Fe5GeTe2 at the interface with graphene with a negative spin polarization. Lateral spin-valve and spin-precession measurements provided unique insights by probing the Fe5GeTe2/graphene interface spintronic properties via spin-dynamics measurements, […]
Using the power of symmetry for new quantum technologies
Phys.org December 15, 2022 In previous research, only one waveguide has been coupled to the qubit with limited access to its symmetries. Researchers in Sweden used two waveguides. They demonstrated a novel coupling scheme between an artificial molecule comprising two identical, strongly coupled transmon qubits and two microwave waveguides. The coupling was engineered so that transitions between states of the same symmetry, with respect to the permutation operator, are predominantly coupled to one waveguide. The coupling selectivity exceeded by a factor of 30 for both waveguides in their device. They showed that it can be used to coherently couple states […]
Energy storage materials built from nano-sized molecular blocks
Phys.org September 20, 2022 Researchers in Sweden have developed a method for producing solid materials from aqueous solutions containing nano-sized niobium molecules, called polyoxoniobates which are water-soluble. They act as molecular building blocks to make a wide range of materials, including supercapacitors that facilitate lithium-ion storage. The nanometer sized molecules can be dissolved in water and spin coated to deposit thin films of niobium pentoxide. When the films are heated to temperatures ranging from 200 to 1200°C, surfaces with varying corrosion resistance and electrochemical properties are obtained. This approach facilitates deposition of alkali-free, metal oxide thin films with varying crystallinity, […]
Research team follows nearly 8,000 paths towards better cell factories
Phys.org April 26, 2022 The inhibitory compounds found in hydrolysates in biomass substantially influence the performance of a cell factory and the economic feasibility of lignocellulosic biofuels and chemicals. Researchers in Sweden analyzed data on Saccharomyces cerevisiae mutants engineered for altered tolerance towards the most common inhibitors found in lignocellulosic hydrolysates: acetic acid, formic acid, furans, and phenolic compounds. The mutants included in the analysis had been shown to display increased or decreased tolerance to individual inhibitors or combinations of inhibitors found in lignocellulosic hydrolysates. Genetic engineering aimed at improving inhibitor or hydrolysate tolerance altered the specific growth rate or […]
Simpler graphene method paves way for new era of nanoelectronics
Phys.org March 15, 2022 The high electron mobility of graphene points to great potential for broadband communications and high-speed electronics operating at terahertz switching rates. However, complex, and expensive fabrication methods make it more expensive and hinder mass production of such devices. Researchers in Sweden proposed chemical vapor deposition (CVD) of graphene on commercial copper (Cu) foils providing a scalable route towards high-quality single-layer graphene. The graphene is grown on a metallic surface like Cu, Pt or Ir, after which it can be separated from the metal and transferred to specifically required substrates. The process can be simply explained as […]
Exotic property of ‘ambidextrous’ crystals points to new magnetic phenomena
Phys.org August 4, 2021 Researchers in Sweden used symmetry-based analysis and numerical computations to predict the existence of antichiral ferromagnetism—a kind of ferromagnetic ordering when both types of chirality (handedness) exist simultaneously and alternate in space. They predicted a fundamentally different magnetic ordering in tetrahedral ferromagnets. They showed that antichiral ferromagnetism can be observed in a class of crystals in which many minerals are formed naturally by studying magnetic ordering in the structure with tetrahedral crystal symmetry and used micromagnetic analysis to derive the new antichiral ordering. The proposed magnetic ordering might result in a rich family of magnetic phenomena […]
Nuclear terrorism could be intercepted by neutron-gamma detector that pinpoints source
EurekAlert May 19, 2021 Researchers in Sweden have developed a Neutron-Gamma Emission Tomography (NGET) system that goes beyond the capabilities of existing radiation portal monitors, by measuring the time and energy correlations between particles emitted in nuclear fission and using machine learning algorithms to visualize where they are coming from. The system looks for coincidences of neutron and gamma ray emissions–which when mapped together in real-time allow pinpointing their origin. They demonstrated the method on a radiation portal monitor prototype system based on fast organic scintillators measuring the characteristic fast time and energy correlations between particles emitted in nuclear fission […]