Phys.org October 27, 2022 Typically, electron transfer proceeds solely through either a metal redox chemistry or an oxygen redox chemistry without the concurrent occurrence of both metal and oxygen redox chemistries in the same electron transfer pathway. An international team of researchers (Singapore, USA – Brookhaven National Laboratory, China) has discovered an electron transfer mechanism that involves a switchable metal and oxygen redox chemistry in nickel-oxyhydroxide-based materials with light as the trigger. The proposed light-triggered coupled oxygen evolution mechanism requires the unit cell to undergo reversible geometric conversion between octahedron (NiO6) and square planar (NiO4) to achieve electronic states with […]
Scientists discover material that can be made like a plastic but conducts like metal
Science Daily October 26, 2022 An international team of researchers (USA – University of Chicago, Stony Brook University, Argonne National Laboratory, South Korea) discovered a way to create a material that can be made like a plastic but conducts electricity more like a metal when they strung nickel atoms like pearls into a string of molecular beads made of carbon and sulfur. The material easily and strongly conducted electricity when heated or chilled or exposed to air and humidity, or even dripped acid and base. But the most striking thing was that the molecular structure of the material was disordered. […]
Stable sodium anodes for sodium metal batteries
Phys.org November 2, 2022 All-solid-state batteries are disadvantaged by their poor physical solid-solid interfacial contact and low ionic conductivity, which restrict their performance and hinder their short-term commercial applicability. Based on the interfacial protection strategy, researchers at UT Austin introduced fluoroethylene carbonate (FEC) into the PDOL system (1,3-Dioxolane (DOL) that can be polymerized through catatonically ring-opening reactions at room temperature to obtain poly(1,3-dioxolane). After the introduction of FEC, the accumulation of reaction products was reduced at the Na metal anode side prior to DOL addition, forming a NaF-rich passivation layer and inhibiting further side reactions between DOL and the Na […]
Study urges caution when comparing neural networks to the brain
MIT News November 2, 2022 The central claims of recent deep learning-based models of brain circuits are that they make novel predictions about neural phenomena or shed light on the fundamental functions being optimized. Through the case-study of grid cells in the entorhinal-hippocampal circuit, a team of researchers in the US (Stanford University, MIT) showed that one often gets neither. They reviewed the principles of grid cell mechanism and function obtained from analytical and first-principles modeling efforts and examined the claims of deep learning models of grid cells. Using large-scale hyperparameter sweeps and theory-driven experimentation, they demonstrated that the results […]
Unipolar quantum optoelectronic devices: Higher speeds in free-space optical communications in the midinfrared band
Phys.org November 2, 2022 A recently demonstrated proof-of-concept of high-speed transmission taking advantage of intersubband devices was limited by the short-distance optical path (up to 1 m). An international team of researchers (France, USA -University of Central Florida, University of New Mexico) used an uncooled quantum cascade detector and a nitrogen-cooled quantum well-infrared photodetector to study the possibility of building a long-range link using unipolar quantum optoelectronics. They evaluated the maximum data rate of their link in a back-to-back configuration before adding a Herriott cell to increase the length of the light path up to 31m. By using pulse shaping, […]
Universal parity quantum computing, a new architecture that overcomes performance limitations
Phys.org October 28, 2022 Researchers in Austria have developed a universal gate set for quantum computing with all-to-all connectivity and intrinsic robustness to bit-flip errors based on parity encoding. They showed that logical controlled phase gate and Rz rotations can be implemented in parity encoding with single-qubit operations. Together with logical Rx rotations, implemented via nearest-neighbor controlled-NOT gates and an Rx rotation, these form a universal gate set. As the controlled phase gate requires only single-qubit rotations, the proposed scheme has advantages for several cornerstone quantum algorithms, e.g., the quantum Fourier transform. They presented a method to switch between different […]
Top 10 Science and Technology Inventions for the Week of October 28, 2022
01. New approach to ‘cosmic magnet’ manufacturing could reduce reliance on rare earths in low-carbon technologies 02. An entangled matter-wave interferometer: Now with double the spookiness 03. Functional carbon materials for addressing dendrite problems in metal batteries 04. Integration on a chip: Miniaturized infrared detectors 05. Meta-lens offers superior off-axis focus 06. The next wonder semiconductor 07. Penguin feathers may be secret to effective anti-icing technology 08. Researchers develop laser that could ‘reshape the landscape of integrated photonics’ 09. A Single Laser Transmitted a Second’s Worth of Internet Traffic in Record Time 10. Tapping hidden visual information: An all-in-one detector […]
An entangled matter-wave interferometer: Now with double the spookiness
Nanowerk October 22, 2022 Researchers at the University of Colorado combined entanglement and delocalization to create a matter-wave interferometer that can sense accelerations with a precision that surpasses the standard quantum limit. In their system each individual atom fell freely under gravity and simultaneously traversed two paths through space while entangled with the other atoms. They demonstrated both quantum non-demolition measurements and cavity-mediated spin interactions for generating squeezed momentum states with directly observed sensitivity 3.4+1.1−0.9 dB and 2.5+0.6−0.6 dB below the standard quantum limit, respectively. They injected an entangled state into a Mach–Zehnder light-pulse interferometer with directly observed sensitivity 1.7+0.5−0.5 dB below the […]
Functional carbon materials for addressing dendrite problems in metal batteries
Phys.org October 25, 2022 Metal batteries that directly use active metals as anodes are promising solutions for energy upgrade of battery technologies, but they suffer from dendrite problems. Researchers in China have demonstrated that functional carbon materials (FCMs) can suppress metal dendrites. They reviewed recent progress in using FCMs to deal with dendrite problems. The review focused on the surface chemistry and multi-dimensional carbon material engineering, which systematically overcomes the problems through diverse methods, such as reinforcing desolvation, improving interface compatibility, homogenizing electric field, buffering volume expansion and lattice mismatch. They refined the long-standing debate about whether surface defects in […]
Insect Swarms Can Electrify The Air as Much as a Thunderstorm
Science Alert October 25, 2022 The atmosphere hosts multiple sources of electric charge that influence critical processes such as the aggregation of droplets and the removal of dust and aerosols. Whereas these electric fields are known to respond to physical and geological processes, the effect of biotic sources of charge has not hitherto been considered. Researchers in the UK combined theoretical and empirical evidence to demonstrate that honeybee swarms directly contribute to atmospheric electricity, in proportion to the swarm density. They provided a quantitative assessment of this finding, by comparing the electrical contribution of various swarming insect species with common […]