Self-healing materials are so widespread that clothes lines and tech companies are already applying them to different products.
Now, a research team at the University of California, Riverside, has developed a new type of self-healing material that is conductive of electricity, highly elastic and almost entirely transparent. The lead researcher has revealed that he drew inspiration from Marvel’s Wolverine character.
Nvidia Corp. is in advanced talks to acquire Arm Ltd., the chip designer that SoftBank Group Corp. bought for $32 billion four years ago, according to people familiar with the matter.
The two parties aim to reach a deal in the next few weeks, the people said, asking not to be identified because the information is private. Nvidia is the only suitor in concrete discussions with SoftBank, according to the people.
A deal for Arm could be the largest ever in the semiconductor industry, which has been consolidating in recent years as companies seek to diversify and add scale. But any deal with Nvidia, which is a customer of Arm, would likely trigger regulatory scrutiny as well as a wave of opposition from other users.
A team of researchers affiliated with multiple institutions in China and one in the U.S. has found that semiconducting crystals of indium selenide (InSe) have exceptional flexibility. In their paper published in the journal Science, the group describes testing samples of InSe and what they learned about the material. Xiaodong Han with Beijing University of Technology has published a Perspective piece outlining the work by the team in China in the same journal issue.
As the researchers note, most semiconductors are rigid, which means they are difficult to use in applications that require varied surfaces or bending. This has presented a problem for portable device makers as they attempt to respond to user demand for bendable electronics. In this new effort, the researchers in China have found one semiconductor, InSe, that is not only flexible, but is so pliable that it can be processed using rollers.
InSe, as its name implies, is a compound made from indium (a metal element often used in touchscreens) and selenium (a non-metal element). Selenium is also a 2-D semiconductor, and has come under scrutiny after researchers discovered that its bandgap matched the visible region in the electromagnetic spectrum. It has previously been studied for use in specialty optoelectronic applications. In this new effort, the researchers looked into the possibility of using it as a semiconductor in bendable portable electronic devices.
We have created a new architected material, which is both highly deformable and ultra‐resistant to dynamic point loads. The bio-inspired metallic cellular structure (with an internal grid of large ceramic segments) is non-cuttable by an angle grinder and a power drill, and it has only 15% steel density. Our architecture derives its extreme hardness from the local resonance between the embedded ceramics in a flexible cellular matrix and the attacking tool, which produces high-frequency vibrations at the interface. The incomplete consolidation of the ceramic grains during the manufacturing also promoted fragmentation of the ceramic spheres into micron-size particulate matter, which provided an abrasive interface with increasing resistance at higher loading rates. The contrast between the ceramic segments and cellular material was also effective against a waterjet cutter because the convex geometry of the ceramic spheres widened the waterjet and reduced its velocity by two orders of magnitude. Shifting the design paradigm from static resistance to dynamic interactions between the material phases and the applied load could inspire novel, metamorphic materials with pre-programmed mechanisms across different length scales.
Researchers have for the first time managed to use electricity to switch on magnetism in a material that’s normally non-magnetic. The find could be a step towards making electronic components out of common materials that might not otherwise be suitable.
Put simply, ferromagnetism – the strongest form of the phenomenon – arises in a material when the majority of electrons in its atoms spin in the same direction. For non-magnetic materials, the electrons are usually paired up so that their opposite spins cancel out the magnetic field.
There aren’t many substances that are natively ferromagnetic, but the most common ones are iron, cobalt and nickel, as well as their alloys. That doesn’t give engineers all that much to work with when creating electronic devices.
Forty-five years after superconductivity was first discovered in metals, the physics giving rise to it was finally explained in 1957 at the University of Illinois at Urbana-Champaign, in the Bardeen-Cooper-Schrieffer (BCS) theory of superconductivity.
Thirty years after that benchmark achievement, a new mystery confronted condensed matter physicists: the discovery in 1987 of copper-oxide or high-temperature superconductors. Now commonly known as the cuprates, this new class of materials demonstrated physics that fell squarely outside of BCS theory. The cuprates are insulators at room temperature, but transition to a superconducting phase at a much higher critical temperature than traditional BCS superconductors. (The cuprates’ critical temperature can be as high as 170 Kelvin—that’s −153.67°F—as opposed to the much lower critical temperature of 4 Kelvin—or −452.47°F—for mercury, a BCS superconductor.)
The discovery of high-temperature superconductors, now more than 30 years ago, seemed to promise that a host of new technologies were on the horizon. After all, the cuprates’ superconducting phase can be reached using liquid nitrogen as a coolant, instead of the far costlier and rare liquid helium required to cool BCS superconductors. But until the unusual and unexpected superconducting behavior of these insulators can be theoretically explained, that promise remains largely unfulfilled.
The possibility of achieving room temperature superconductivity took a tiny step forward with a recent discovery by a team of Penn State physicists and materials scientists.
The surprising discovery involved layering a two-dimensional material called molybdenum sulfide with another material called molybdenum carbide. Molybdenum carbide is a known superconductor—electrons can flow through the material without any resistance. Even the best of metals, such as silver or copper, lose energy through heat. This loss makes long-distance transmission of electricity more costly.
“Superconductivity occurs at very low temperatures, close to absolute zero or 0 Kelvin,” said Mauricio Terrones, corresponding author on a paper in Proceedings of the National Academy of Sciences published this week. “The alpha phase of Moly carbide is superconducting at 4 Kelvin.”
Materials scientists studying recharging fundamentals made an astonishing discovery that could open the door to better batteries, faster catalysts and other materials science leaps.
Scientists from the University of California San Diego and Idaho National Laboratory scrutinized the earliest stages of lithium recharging and learned that slow, low-energy charging causes electrodes to collect atoms in a disorganized way that improves charging behavior. This noncrystalline “glassy” lithium had never been observed, and creating such amorphous metals has traditionally been extremely difficult.
The findings suggest strategies for fine-tuning recharging approaches to boost battery life and—more intriguingly—for making glassy metals for other applications. The study was published on July 27 in Nature Materials.
Discovery by scientists at Berkeley Lab, UC Berkeley could help find silicon’s successor in race against Moore’s Law.
In the search for new materials with the potential to outperform silicon, scientists have wanted to take advantage of the unusual electronic properties of 2D devices called oxide heterostructures, which consist of atomically thin layers of materials containing oxygen.
Scientists have long known that oxide materials, on their own, are typically insulating – which means that they are not electrically conductive. When two oxide materials are layered together to form a heterostructure, new electronic properties such as superconductivity – the state in which a material can conduct electricity without resistance, typically at hundreds of degrees below freezing – and magnetism somehow form at their interface, which is the juncture where two materials meet. But very little is known about how to control these electronic states because few techniques can probe below the interface.
