The results provide a foundation for further development, but several challenges remain. The researchers want to reduce cracking, improve durability, and determine how to manufacture more complicated shapes.
“The approach of forming metal materials by softening them rather than fully melting them is novel, and it has the potential to be applied not only to cemented carbides, which were the focus of this study, but also to other materials,” said Marumoto.
Fusion systems need inner walls that can withstand extreme heat. One promising solution uses liquid lithium to protect the walls, held like water in a sponge made of the exceptionally strong metal tungsten. An advanced manufacturing process can be used to make tungsten into sponge-like wall tiles with lots of pores for flowing liquid lithium. But this process also leaves the tungsten contaminated with other materials, such as carbon, oxygen or nitrogen.
When exposed to liquid lithium, the carbon and oxygen react to form solids that can plug the holes in the tungsten, preventing the lithium from flowing properly. Even if the tungsten were cleaned at the end of the manufacturing process, it would become recontaminated when the tiles are exposed to air during installation.
Now researchers from the U.S. Department of Energy’s Princeton Plasma Physics Laboratory (PPPL), Princeton University and Pennsylvania State University have found a clever way to clean those tiles after they are installed and sealed inside the fusion system—in vacuum chambers from which the air has been removed. The advance, which uses heat combined with particles from a neon plasma to knock contaminants out of tiles, could help future fusion systems run better with liquid lithium.
Modern photonic chips can pack sophisticated optical functions onto devices smaller than a fingernail. They are increasingly used to generate, manipulate and measure light for applications ranging from communications to sensing. But most of these chips rely on a single material to do the heavy lifting, limiting the range of optical effects they can produce.
Researchers have now demonstrated a different approach: letting two materials share the work. As reported in Advanced Photonics, scientists combined two nonlinear optical effects that normally occur separately. Their device uses a silicon nitride core to generate optical frequency combs while a surrounding silica layer produces Raman scattering.
By harnessing the strengths of both materials at once, the team created a new type of integrated photonic device capable of generating broad ranges of light frequencies on a chip.
First-of-its-kind, data-driven machine learning model reveals in fine detail the pathway that solid-state reactions take.
There are few treatment options available for people with disorders of the esophagus. Delivering drugs directly to this part of the body is difficult, so patients are usually treated with systemic drugs, which can have unwanted side effects.
To overcome that challenge, MIT engineers developed a gel-like oral drug formulation that can coat the mucosal lining of the esophagus after being swallowed, allowing drugs to pass through the tissue.
The formulation, which includes a hydrogel and other key ingredients that promote rapid drug absorption, could be used to deliver antibodies including infliximab, used to treat a number of autoimmune diseases, or other types of antibodies or small-molecule drugs.
A world-first photonic time crystal can reshape light almost instantly, opening a path toward ultrafast optical technology.
An international research team has created the first experimentally demonstrated all-optical photonic time crystal (PTC), a material whose optical behavior can be altered strongly and repeatedly over extremely short periods of time.
The work, carried out by scientists from École Polytechnique, Collège de France, and Helmholtz-Zentrum Dresden-Rossendorf (HZDR), was published in Nature. The researchers used HZDR’s TELBE superradiant terahertz source to push the material into a previously unexplored form of light-matter interaction in the terahertz range.
Engineering Coordination Under Capability Gradients and Structural Turbulence. A formal framework for institutional coordination in the age of AGI.
The Earth is akin to a rocky, molten-in-the-middle nesting doll – or perhaps a rotting, soft-centered onion, though the latter analogy affords our majestic planet much less dignity.
Although only several handfuls (39 fingers’ worth, to be exact) of people have alighted on the ocean’s deepest depths or upon the surface of the Moon, there’s one relatively nearby alien environment that no human will ever personally explore: the Earth’s core.
Approaching it, each Earthly layer differs in composition and increases in pressure and temperature, displaying unique material properties that become murkier the deeper we delve.
To achieve the ultra-fast changes needed, they hit the metamaterial with powerful laser pulses. This violently accelerated the material’s free-floating electrons, dynamically altering their energy and making their “effective mass” shift by up to 80% of their rest mass in fractions of a trillionth of a second. This massive, rapid shift forced the material into a time-crystal state.
A plasmonic metamaterial driven at terahertz frequencies achieves strong, ultrafast temporal modulation and shows a transition to the photonic time crystal regime with reduced plasmonic losses.
