SemiconductorScientists have figured out how to make tiny individual films—each just a few atoms high—and stack them for use in new kinds of electronics.

Over the past half-century, scientists have shaved silicon films down to just a wisp of atoms in pursuit of smaller, faster electronics. For the next set of breakthroughs, though, they’ll need new ways to build even tinier and more powerful devices.

In a study that appears in Nature, researchers describe an innovative method to make stacks of thin, uniform layers of semiconductors just a few atoms thick which could expand capabilities for devices like solar cells and cell phones.

Stacking thin layers of materials offers a range of possibilities for making electronic devices with unique properties. But manufacturing them is a delicate process, with little room for error, researchers say.

“The scale of the problem we’re looking at is, imagine trying to lay down a flat sheet of plastic wrap the size of Chicago without getting any air bubbles in it,” says Jiwoong Park, a professor of chemistry at the University of Chicago and at the Institute for Molecular Engineering and the James Franck Institute. “When the material itself is just atoms thick, every little stray atom is a problem.”

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RocketA team of engineers from Monash University have successfully test-fired the world’s first 3D printed rocket engine. By utilizing a unique aerospike design, the team, led by ECS fellow Nick Birbilis, was able to increase efficiency levels over that of traditional bell-shaped rockets.

This from The Standard:

Its design works by firing the gases along a spike and using atmospheric pressure to create a virtual bell.

The shape of the spike allows the engine to maintain high efficiency over a wider range of altitude and air pressures. It’s a much more complex design but is difficult to build using traditional technology.

Read the full article.

“We were able to focus on the features that boost the engine’s performance, including the nozzle geometry and the embedded cooling network,” Birbilis says. “These are normally balanced against the need to consider how on earth someone is going to manufacture such a complex piece of equipment. Not so with additive manufacturing. Going from concept to testing in just four months is an amazing achievement.”

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IdeaBig ideas are getting harder and harder to find, and innovations have become increasingly massive and costly endeavors, according to new research.

As a result, tremendous continual increases in research and development will be needed to sustain even today’s low rate of economic growth.

This means modern-day inventors—even those in the league of Steve Jobs—will have a tough time measuring up to the productivity of the Thomas Edisons of the past.

Nicholas Bloom, senior fellow at the Stanford Institute for Economic Policy Research and coauthor of a paper released this week by the National Bureau of Economic Research, contends that so many game-changing inventions have appeared since World War II that it’s become increasingly difficult to come up with the next big idea.

“The thought now of somebody inventing something as revolutionary as the locomotive on their own is inconceivable,” Bloom says.

“It’s certainly true if you go back one or two hundred years, like when Edison invented the light bulb,” he says. “It’s a massive piece of technology and one guy basically invented it. But while we think of Steve Jobs and the iPhone, it was a team of dozens of people who created the iPhone.”

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A new device that runs on almost zero power can transmit data across distances of up to 2.8 kilometers—breaking a long-held barrier—and could lead to a vast array of interconnected devices.

For example, flexible electronics—such as knee patches that capture range of motion in arthritic patients or patches that use sweat to detect fatigue in athletes and soldiers—hold great promise for collecting medically relevant data.

But today’s flexible electronics and other sensors that can’t employ bulky batteries and need to operate with very low power typically can’t communicate with other devices more than a few feet or meters away. This limits their practical use in applications for medical monitoring, home sensing to smart cities, and precision agriculture.

By contrast, the new long-range backscatter system, which uses reflected radio signals to transmit data at extremely low power and low cost, achieve reliable coverage throughout a 4,800-square-foot house, an office area covering 41 rooms, and a one-acre vegetable farm.

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DataResearchers have developed a new way to alleviate many of the issues that make magnetic data storage for computer hard disks and other data storage hardware problematic, including speed and energy use.

For almost seventy years now, magnetic tapes and hard disks have been used for data storage in computers. In spite of many new technologies that have arisen in the meantime, the controlled magnetization of a data storage medium remains the first choice for archiving information because of its longevity and low price.

As a means of realizing random access memories (RAMs), however, which are used as the main memory for processing data in computers, magnetic storage technologies have long been considered inadequate. That is mainly due to its low writing speed and relatively high energy consumption.

Pietro Gambardella, professor at the materials department of ETH Zurich, and his colleagues, have now shown that using a novel technique, faster magnetic storage is possible without wasting energy.

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Chemical engineers have generated ultra-pure green light for the first time.

The new light-emitting diode paves the way for visibly improved color quality in a new generation of ultra-high definition displays for TVs and smartphones.

Electronic devices must first be able to produce ultra-pure red, blue, and green light in order to enable the next generation of displays to show images that are clearer, sharper, richer in detail, and with a more refined range of colors. For the most part, this is already possible for red and blue light; green light, however, has been at the limits of technology.

This is due mainly to human perception, since the eye is able to distinguish between more intermediary green hues than red or blue ones. “This makes the technical production of ultra-pure green very complex, which creates challenges for us when it comes to developing technology and materials,” says Sudhir Kumar of ETH Zurich, co-lead author of the study.

Ultra-pure green plays a key role in extending the color range, or gamut. Ultimately, new hues arise from the technical mixture of three base colors: red, blue, and green. The purer the base colors, the broader the range of hues a screen can display. The new LED is in line with 97 to 99 percent of the international standard for Ultra HD, Rec.2020. By comparison, the purest color TV displays currently available on the market cover on average only 73.11 to 77.72 percent; none exceeds 80 percent.

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MicroscopeA team of engineers has found a simple, economical way to make a nano-sized device that can lift many times its own weight.

Their creation weighs 1.6 milligrams (about as much as five poppy seeds) and can lift 265 milligrams (the weight of about 825 poppy seeds) hundreds of times in a row.

Its strength comes from a process of inserting and removing ions between very thin sheets of molybdenum disulfide (MoS2), an inorganic crystalline mineral compound. It’s a new type of actuator—devices that work like muscles and convert electrical energy to mechanical energy.

The discovery—an “inverted-series-connected (ISC) biomorph actuation device”—appears in Nature.

“We found that by applying a small amount of voltage, the device can lift something that’s far heavier than itself,” says Manish Chhowalla, professor and associate chair of the materials science and engineering department of in the School of Engineering at Rutgers University.

“This is an important finding in the field of electrochemical actuators. The simple restacking of atomically thin sheets of metallic MoS2 leads to actuators that can withstand stresses and strains comparable to or greater than other actuator materials.”

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MedicineResearchers have developed a new method for evaluating drug safety that can detect stress on cells at earlier stages than current methods, which mostly rely on detecting cell death.

The new method uses a fluorescent sensor that is turned on in a cell when misfolded proteins begin to aggregate—an early sign of cellular stress. The method can be adapted to detect protein aggregates caused by other toxins as well as diseases such as Alzheimer’s or Parkinson’s.

“Drug-induced protein stress in cells is a key factor in determining drug safety,” says senior author Xin Zhang, assistant professor of chemistry and of biochemistry and molecular biology at Penn State.

“Drugs can cause proteins—which are long strings of amino acids that need to be precisely folded to function properly—to misfold and clump together into aggregates that can eventually kill the cell. We set out to develop a system that can detect these aggregates at very early stages and that also uses technology that is affordable and accessible to many laboratories,” Zhang says.

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Researchers have found a way to use magnetic nanoparticle clusters to punch through biofilms to reach bacteria that can foul water treatment systems.

The nanoclusters then deliver bacteriophages—viruses that infect and propagate in bacteria—to destroy the bacteria, usually resistant to chemical disinfection.

Without the pull of a magnetic host, these “phages” disperse in solution, largely fail to penetrate biofilms and allow bacteria to grow in solution and even corrode metal, a costly problem for water distribution systems.

The Rice University lab of environmental engineer Pedro Alvarez and colleagues in China developed and tested clusters that immobilize the phages. A weak magnetic field draws them into biofilms to their targets.

“This novel approach, which arises from the convergence of nanotechnology and virology, has a great potential to treat difficult-to-eradicate biofilms in an effective manner that does not generate harmful disinfection byproducts,” Alvarez says.

Biofilms can be beneficial in some wastewater treatment or industrial fermentation reactors owing to their enhanced reaction rates and resistance to exogenous stresses, says graduate student and co-lead author Pingfeng Yu.

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LightA new device improves on the sensitivity and versatility of sensors that detect doping in athletics, bomb-making chemicals, or traces of drugs. It could also cut costs.

To conduct these kinds of searches, scientists often shine light on the materials they’re analyzing. This approach is known as spectroscopy, and it involves studying how light interacts with trace amounts of matter.

One of the more effective types of spectroscopy is infrared absorption spectroscopy, which scientists use to sleuth out performance-enhancing drugs in blood samples and tiny particles of explosives in the air.

While infrared absorption spectroscopy has improved greatly in the last 100 years, researchers are still working to improve the technology.

“This new optical device has the potential to improve our abilities to detect all sorts of biological and chemical samples,” says Qiaoqiang Gan, associate professor of electrical engineering in the School of Engineering and Applied Sciences at University at Buffalo. Gan is lead author of the study.

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