Lifeboat Foundation

Researchers at the Department of Energy’s SLAC National Accelerator Laboratory and Stanford University have created a new type of quantum material whose atomic scaffolding, or lattice, has been dramatically warped into a herringbone pattern.

The resulting distortions are “huge” compared to those achieved in other materials, said Woo Jin Kim, a postdoctoral researcher at the Stanford Institute for Materials and Energy Sciences (SIMES) at SLAC who led the study.

“This is a very fundamental result, so it’s hard to make predictions about what may or may not come out of it, but the possibilities are exciting,” said SLAC/Stanford Professor and SIMES Director Harold Hwang.

A supermassive black hole at the centre of a galaxy some 8.5 billion years way has ripped apart a nearby star, producing some of the most luminous jets ever seen.

When stars and other objects stray too close to a supermassive black hole they are destroyed by the black hole’s immense gravity.

These occurrences, known as tidal-disruption events (TDEs), result in a circling disk of material that is slowly pulled into the black hole and very occasionally, as in the case of supermassive black hole AT2022cmc, ejecting bright beams of material travelling close to the speed of light.

A novel crystalline material is readily grown from low-melting-temperature mixtures—a result that points toward a new route to above-room-temperature ferromagnets.

Researchers at Purdue University have discovered new waves with picometer-scale spatial variations of electromagnetic fields which can propagate in semiconductors like silicon. The research team, led by Dr. Zubin Jacob, Elmore Associate Professor of Electrical and Computer Engineering and Department of Physics and Astronomy (courtesy) published their findings in APS Physics Review Applied in a paper titled, “Picophotonics: Anomalous Atomistic Waves in Silicon.”

“The word microscopic has its origins in the length scale of a micron which is a million times smaller than a meter. Our work is for light matter interaction within the picoscopic regime which is far smaller, where the discrete arrangement of atomic lattices changes light’s properties in surprising ways.” says Jacob.

These intriguing findings demonstrate that natural media host a variety of rich light-matter interaction phenomena at the atomistic level. The use of picophotonic waves in semiconducting materials may lead researchers to design new, functional optical devices, allowing for applications in quantum technologies.

Advances in computing power over the decades have come thanks in part to our ability to make smaller and smaller transistors, a building block of electronic devices, but we are nearing the limit of the silicon materials typically used. A new technique for creating 2D oxide materials may pave the way for future high-speed electronics, according to an international team of scientists.

“One way we can make our transistors, our electronic devices, work faster is to shrink the distance electrons have to travel between point A and B,” said Joshua Robinson, professor of materials science and engineering at Penn State. “You can only go so far with 3D materials like silicon—once you shrink it down to a nanometer, its properties change. So there’s been a massive push looking at new materials, one of which are 2D materials.”

The team, led by Furkan Turker, graduate student in the Department of Materials Sciences, used a technique called confinement hetroepitaxy, or CHet, to create 2D oxides, materials with special properties that can serve as an atomically thin insulating layer between layers of electrically conducting materials.

Prof. Wang Hui, together with Prof. Lin Wenchu and associate Prof. Qian Junchao from the Hefei Institutes of Physical Science (HFIPS) of the Chinese Academy of Sciences, have recently reported a near infrared (NIR)-II-responsive carbon-coated iron oxide nanocluster that was guided by magnetic resonance imaging and capable of combined photothermal and chemodynamic therapy (CDT), for synergistic cancer treatment.

The results were published in SCIENCE CHINA Materials.

As a promising treatment strategy, CDT has become a hot spot in cancer research due to its simple operation and low side effects. The basic principle of CDT is that the nanozymes activate the intracellular Fenton reaction, leading to the over-production of hydroxyl radicals, which are toxic to cancer cells. Magnetite nanocrystals are widely used as Fenton reagents due to their non-invasive imaging ability and good biocompatibility. However, the ferromagnetic behavior and easy oxidization of magnetite nanocrystals lead to colloidal instability as nanozymes and limit the imaging-guided cancer therapy in practical applications.

Physicists at the University of Wisconsin-Madison have directly measured the fluid-like flow of electrons in graphene at nanometer resolution for the first time. The results appear in the journal Science today.

Graphene, an atom-thick sheet of carbon arranged in a honeycomb pattern, is an especially pure electrical conductor, making it an ideal material to study electron flow with very low resistance. Here, researchers intentionally add impurities at known distances, and find that electron flow changes from gas-like to fluid-like as the temperature rises.

“All conductive materials contain impurities and imperfections that block electron flow, which causes resistance. Historically, people have taken a low-resolution approach to identifying where resistance comes from,” says Zach Krebs, a physics graduate student at UW-Madison and co-lead author of the study. “In this study, we image how charge flows around an impurity and actually see how that impurity blocks current and causes resistance, which is something that hasn’t been done before to distinguish gas-like and fluid-like electron flow.”

A well-known mineral is once again the center of attention thanks to applications in electronics: the Vienna University of Technology shows that mica still possesses some surprises.

At first glance, mica appears to be quite ordinary: it is a prevalent mineral found in materials like granite and has undergone extensive examination from geological, chemical, and technical standpoints.

At first, it may seem that there’s nothing groundbreaking that can be uncovered about such a commonplace material. However, a team from the Vienna University of Technology has recently published a study in Nature Communications.

Vibrations are the main drivers of a mysterious process in which a liquid flow generates an electric current in the solid below it.

Liquid flowing over a conducting surface is known to produce electric currents, but the mechanism behind this effect has been unclear. New experiments with a single liquid drop dragged over a graphene surface demonstrate that viscous forces at the liquid–solid interface create vibrations, or phonons, in the graphene sheet that drag electrons in the direction of the flow [1]. The researchers verified this “phonon wind” interpretation by observing multiple liquids and by testing graphene surfaces with and without wrinkles. The results could lead to highly sensitive flow sensors or to devices that can harvest electricity from flows.

Researchers have found that water flowing over a material—in particular, carbon nanotubes or graphene—can generate electric currents in the solid. The effect appears in carbon materials because the surfaces are atomically flat and thus allow the liquid to flow largely unobstructed at the liquid–solid boundary, explains Alessandro Siria from the École Normale Supérieure in France. Several models have been proposed to explain the flow-induced currents, often involving charges within the liquid acting on the electrons in the solid. However, experimental uncertainties have prevented researchers from determining which model is best.