Researchers have measured graphene’s plasmon spectrum using a novel electron-based spectroscopy technique.
Category: materials – Page 5
GE Aerospace is advancing hypersonic flight with plans to scale up its dual-mode ramjet technology in 2025.
To create a full propulsion system, engineers will improve sophisticated controls and use state-of-the-art materials from jet engine advancements in the upcoming months. This will be a crucial step in reaching flying capabilities.
An sophisticated hypersonic dual-mode ramjet that can handle high-speed, long-range flying across a variety of multi-mission aircraft was unveiled by GE Aerospace in July 2024.
Physicists developed a method using hydrogen cations to control electronic properties in magnetic Weyl semimetals, enabling advanced quantum technologies.
Stanford researchers have uncovered a new material, niobium phosphide, that surpasses copper in electrical conductivity when fashioned into ultrathin films.
This breakthrough could revolutionize the efficiency and performance of future electronics by alleviating the limitations posed by traditional metal wires in nanoscale circuits.
Nanoscale Electronics Challenges
Three exotic new species of superconductivity were spotted last year, illustrating the myriad ways electrons can join together to form a frictionless quantum soup.
Molecular crystals with conductivity and magnetism, due to their low impurity concentrations, provide valuable insights into valence electrons. They have helped link charge ordering to superconductivity and to explore quantum spin liquids, where electron spins remain disordered even at extremely low temperatures.
Valence electrons with quantum properties are also expected to exhibit emergent phenomena, making these crystals essential for studying novel material functionalities.
However, the extent to which valence electrons in molecular crystals contribute to magnetism remains unclear, leaving their quantum properties insufficiently explored. To address this, a research team used light to analyze valence electron arrangements, building on studies of superconductors and quantum spin liquids. The findings are published in Physical Review B.
Stars are born in clouds of gas and dust, making it difficult to observe their early development. But researchers at Chalmers have now succeeded in simulating how a star with the mass of the sun absorbs material from the surrounding disk of material—a process called accretion.
Researchers at Duke University have uncovered the molecular inner workings of a material that could underpin next-generation rechargeable batteries.
Unlike today’s popular lithium-ion batteries that feature a liquid interior, the lithium-based compound is a solid at operational temperatures. But despite its rigid interior structure, charged ions are still able to quickly travel through, making it a “super ionic” material. While researchers have been interested in this compound for some time, they have not known how lithium ions are able to pass through its solid crystalline structure so easily.
The new results answer many standing questions, showing surprising liquid-like behavior at the atomic level. With these insights in hand, as well as the machine learning models used to obtain them, researchers are set to explore similar recipes to solve many of the field’s long-standing challenges.
T Coronae Borealis (T CrB) is a binary star system comprising two stars at very different stages of their life cycles: a red giant and a white dwarf. The red giant, an aging star, is expanding as it nears the end of its life, shedding layers of material into space. Meanwhile, the white dwarf, a stellar remnant that has burned through its fuel, is steadily cooling. This system draws the red giant’s expelled material toward the white dwarf’s surface. When enough accumulates, it triggers a thermonuclear explosion, creating a dramatic outburst of energy and light.
Astronomers know about the “Blaze Star” because it’s had sudden outbursts before. They even know there is usually a decade-long uptick in brightness before the explosion, preceded by a noticeable dip in brightness. That 10-year uptick was reported in a paper in 2023, while the American Association of Variable Star Observers announced T CrB’s pre-eruption dip in April 2024.
Something to bear in mind is that this is a rare astronomical event, but only committed stargazers are likely to get much out of it.
Dipole toroidal modes are a unique set of excitations that are predicted to occur in various physical systems, ranging from atomic nuclei to metamaterials. What characterizes these excitations, or modes, is a toroidal distribution of currents, which results in the formation of vortex-like structures.
A classic example is smoke rings, the characteristic “rings” of smoke produced when puffs of smoke are released into the air through a narrow opening. Physics theories have also predicted the existence of toroidal dipole excitations in atomic nuclei, yet observing these modes has so far proved challenging.
Researchers at Technische Universitat Darmstadt, the Joint Institute for Nuclear Research, and other institutes recently identified candidates for toroidal dipole excitations in the nucleus 58 Ni for the very first time. Their paper, published in Physical Review Letters, opens new possibilities for the experimental observations of these elusive modes in heavy nuclei.