Phys.org March 10, 2022 In high-temperature superconductors, at a certain “critical point,” electrons seem to vanish from the Fermi surface map. To understand this phenomenon and engineer that property into some other material that is easier to adopt in technologies, an international team of researchers (USA – Cornell University, UT Austin, National High Magnetic Field Laboratory, Binghamton University, Canada, France, UK) discovered that magnetism is key to understanding the behavior of electrons in “high-temperature” superconductors. They measured the Fermi surface of a copper-oxide high temperature superconductor as a function of electron concentration, right around the critical point and found that […]
Quantum information: Light from rare-earth molecules
Nanowerk March 11, 2022 Rare-earth ions (REIs) are promising solid-state systems for building light–matter interfaces at the quantum level. However, few crystalline materials have shown an environment quiet enough to fully exploit REI properties. Molecular systems can provide such capability but generally lack spin states and they show broad optical lines that severely limit optical-to-spin coherent interfacing. An international team of researchers (France, Germany) found that europium molecular crystals exhibit linewidths in the tens of kilohertz range, orders of magnitude narrower than those of other molecular systems. They harnessed this property to demonstrate efficient optical spin initialization, coherent storage of […]
Researchers Set Record by Preserving Quantum States in Silicon Carbide for More Than Five Seconds
SciTech Daily March 13, 2022 Inability to easily read the information held in qubits, and the short coherence of qubits are impediments to the many technological applications of quantum science such as hacker proof communications networks and quantum computers. An international team of researchers (USA – University of Chicago, Argonne National Laboratory, Japan, Sweden) has demonstrated single-shot readout of single defects in SiC via spin-to-charge conversion, whereby the defect’s spin state was mapped onto a long-lived charge state. With this technique, they achieved over 80% readout fidelity without pre- or post-selection, resulting in a high signal-to-noise ratio that enabled them […]
Revealing thermal runaway routes in lithium-sulfur batteries
EurekAlert March 14, 2022 Researchers in China investigated the thermal runaway behavior of Li-S pouch cells from the materials level and found that the thermal runaway route starts from cathode-induced reactions and then gets accelerated by reactions from the anode. The solvent vaporization was verified to dominate pressure building up during thermal runaway. Li-S batteries employing varied electrolytes with different thermal stabilities, even inorganic all solid-state electrolytes, all undergo rapid thermal runaway at a narrow temperature range due to the intrinsic thermal features of the sulfur cathode and Li metal anode sublimating, melting, and cross-reacting at high temperatures. According to […]
‘Self-driving’ lab speeds up research, synthesis of energy materials
Science Daily March 16, 2022 A team of researchers in the US (North Carolina State University, University of Buffalo) has developed and demonstrated a ‘self-driving lab’ that uses artificial intelligence and fluidic systems to advance our understanding of metal halide perovskite (MHP) nanocrystal using cesium lead halides for proof of concept. The self-driving lab technology can autonomously dope MHP nanocrystals with varying levels of manganese which changes the optical and electronic properties of the nanocrystals and introduces magnetic properties to the material. Thus, giving control over greater range of electronic and magnetic properties. The autonomous system could also be used […]
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 […]
‘Sky is not the limit’ for solar geoengineering
Science Daily March 14, 2022 In a report a team of researchers in the US (Yale College Harvard University, AIAA, industry) responded to a question posed by the US National Academy of Science, Engineering, and Medicine in a landmark study in March 2021 which recognized the need for additional research on the viability of depositing aerosols well above 20 km to deflect incoming sunlight and countervail global warming. According to the team airliners and military jets routinely cruise near 10 km, whereas 20 km is the realm of high-flying spy planes and drones. Planning to fly hundreds of thousands of […]
UCLA materials scientists lead global team in finding solutions to biggest hurdle for solar cell technology
EurekAlert March 15, 2022 Optoelectronic devices consist of heterointerfaces formed between dissimilar semiconducting materials. The relative energy level alignment between contacting semiconductors determinately affects the heterointerface charge injection and extraction dynamics. For perovskite solar cells (PSCs), the heterointerface between the top perovskite surface and a charge-transporting material (CTM) is often treated for defect passivation to improve PSC stability and performance. However, such surface treatments could also affect the heterointerface energetics. An international team of researchers (USA – UCLA, UC Irvine, Turkey, South Korea, Taiwan) has shown that surface treatments may induce a negative work function shift (i.e., more n-type), which […]
Top 10 Science and Technology Inventions for the Week of March 11, 2022
01. Breakthrough in quantum sensing provides new material to make qubits 02. Exploring the bounds of room-temperature superconductivity 03. ‘Fingerprint’ machine learning technique identifies different bacteria in seconds 04. Form-free metasurfaces enable novel and intelligent optical illusion 05. The future of data storage is double-helical, research indicates 06. Physicists show how frequencies can easily be multiplied without special circuitry 07. Researchers design charged ‘power suits’ for electric vehicles and spacecraft 08. Robot ‘bugs’ that can go just about anywhere 09. Study raises new possibilities for triggering room-temperature superconductivity with light 10. Vacuum fluctuations break topological protection And others… Analysis suggests […]
Analysis suggests China has passed US on one research measure
Phys.org March 8, 2022 The top-1% most-highly-cited articles are watched closely as the vanguards of the sciences. However, this finding contrasts with repeated reports of Western agencies that the quality of China’s output in science is lagging other advanced nations, even as it has caught up in numbers of articles. An international team of researchers (USA -Ohio State University, China, the Netherlands) used field normalizations, a new measurement method, which classify source journals by discipline. Classifications can be used for the decomposition, but not for the normalization. When the data is thus decomposed, the USA ranks ahead of China in […]