Rice University researchers have developed an innovative solution to a pressing environmental challenge: removing and destroying per- and polyfluoroalkyl substances (PFAS), commonly called “forever chemicals.”
Category: materials – Page 44
Researchers propose a simple magnetic switch using altermagnets
Controlling magnetism in a device is not easy; unusually large magnetic fields or lots of electricity are needed, which are bulky, slow, expensive and/or waste energy. But that looks soon to change, thanks to the recent discovery of altermagnets. Now scientists are putting forth ideas for efficient switches to manage magnetism in devices.
Magnetism has traditionally come in two varieties: ferromagnetism and antiferromagnetism, based on the alignment (or not) of magnetic moments in a material. Early last year, physicists announced experimental evidence for a third variety of magnetism: altermagnetism, a different combination of spins and crystal symmetries. Researchers are now learning how to tune altermagnets, bringing science closer towards practical applications.
We’re all familiar with ferromagnetism (FM), like a refrigerator magnet or compass needle, where magnetic moments in atoms lined up in parallel in a crystal. A second class was added about a hundred years ago called antiferromagnetism (AFM), where magnetic moments in a crystal align regularly in alternate directions on differing sublattices, so the crystal has no net magnetization, but usually does at low temperatures.
Rare quantum state spotted, thanks to thermopower signals in graphene
Such findings wouldn’t have been possible using the traditional resistivity approach. “We demonstrate that the magneto-thermopower detection of fractional quantum Hall states is more sensitive than resistivity measurements,” the researchers note.
“Overall, our findings reveal the unique capabilities of thermopower measurements, introducing a new platform for experimental and theoretical investigations of correlated and topological states in graphene systems, including moiré materials,” Ghahari concluded.
Hopefully, these findings will help us realize the true potential of the FQH effect. However, whether the same approach could be used to detect other exotic quantum states remains to be explored through further research.
The hidden superconducting state in NbSe₂: Shedding layers and gaining insights
Researchers have discovered an unexpected superconducting transition in extremely thin films of niobium diselenide (NbSe2). Publishing in Nature Communications, they found that when these films become thinner than six atomic layers, superconductivity no longer spreads evenly throughout the material, but instead becomes confined to its surface.
This discovery challenges previous assumptions and could have important implications for understanding superconductivity and developing advanced quantum technologies.
Researchers at the Hebrew University of Jerusalem have made a surprising discovery about how superconductivity behaves in extremely thin materials. Superconductors are materials that allow electric current to flow without resistance, which makes them incredibly valuable for technology. Usually, the properties of superconductors change predictably when the materials become thinner; however, this study found something unexpected.
These Electronics-free Robots Can Walk Right Off the 3D-Printer
Imagine a robot that can walk, without electronics, and only with the addition of a cartridge of compressed gas, right off the 3D-printer. It can also be printed in one go, from one material.
That is exactly what roboticists have achieved in robots developed by the Bioinspired Robotics Laboratory at the University of California San Diego. They describe their work in an advanced online publication in the journal Advanced Intelligent Systems.
To achieve this feat, researchers aimed to use the simplest technology available: a desktop 3D-printer and an off-the-shelf printing material. This design approach is not only robust, it is also cheap—each robot costs about $20 to manufacture.
Revolutionary self-healing hydrogel regenerates like human skin
Natural biological tissues, like human skin, possess a unique combination of properties that synthetic materials struggle to replicate. Skin is strong yet flexible and, most impressively, capable of self-repair. Until now, scientists have only been able to replicate either the stiffness of biological tissues or their self-healing ability—but never both at once.
Hydrogels have many advantages, such as biocompatibility, nutrient transport, and ionic conductivity. These features make them promising materials for biomedical applications, but their mechanical limitations have kept them from reaching their full potential.
Most self-healing hydrogels are too soft, with a Young’s modulus below 100 kilopascals (kPa). Others that achieve stiffness above 100 megapascals (MPa) typically lose their ability to heal.
Superelastic alloy that functions in extreme temperatures could aid space exploration
Researchers at Tohoku University have developed a titanium-aluminum (Ti-Al)-based superelastic alloy. This new material is not only lightweight but also strong, offering the unique superelastic capability to function across a broad temperature range—from as low as −269°C, the temperature of liquid helium, to +127°C, which is above the boiling point of water.