materials science (47)

ALPS and Dark Matter...


Magnet row of the ALPS experiment in the HERA tunnel: In this part of the magnets, intense laser light is reflected back and forth, from which axions are supposed to form. Credit: DESY, Marta Maye

Topics: Dark Matter, Materials Science, Particle Physics, Quantum Mechanics

The ALPS (Any Light Particle Search) experiment, which stretches a total length of 250 meters, is looking for a particularly light type of new elementary particle. The international research team wants to search for these so-called axions or axion-like particles using twenty-four recycled superconducting magnets from the HERA accelerator, an intense laser beam, precision interferometry, and highly sensitive detectors.

Such particles are believed to react only extremely weakly with known kinds of matter, which means they cannot be detected in experiments using accelerators. ALPS is therefore resorting to an entirely different principle to detect them: in a strong magnetic field, photons—i.e., particles of light—could be transformed into these mysterious elementary particles and back into [light] again.

"The idea for an experiment like ALPS has been around for over 30 years. By using components and the infrastructure of the former HERA accelerator, together with state-of-the-art technologies, we are now able to realize ALPS II in an international collaboration for the first time," says Beate Heinemann, Director of Particle Physics at DESY.

Helmut Dosch, Chairman of DESY's Board of Directors, adds, "DESY has set itself the task of decoding matter in all its different forms. So ALPS II fits our research strategy perfectly, and perhaps it will push open the door to dark matter."

The ALPS team sends a high-intensity laser beam along a device called an optical resonator in a vacuum tube, approximately 120 meters in length, in which the beam is reflected backward and forwards and is enclosed by twelve HERA magnets arranged in a straight line. If a photon were to turn into an axion in the strong magnetic field, that axion could pass through the opaque wall at the end of the line of magnets.

Once through the wall, it would enter another magnetic track almost identical to the first. Here, the [axion] could then change back into a photon, which would be captured by the detector at the end. A second optical resonator is set up here to increase the probability of an [axion[ turning back into a photon by a factor of 10,000.

This means if [light] does arrive behind the wall, it must have been an axion in between. "However, despite all our technical tricks, the probability of a photon turning into an axion and back again is very small," says DESY's Axel Lindner, project leader and spokesperson of the ALPS collaboration, "like throwing 33 dice and them all coming up the same."

In order for the experiment to actually work, the researchers had to tweak all the different components of the apparatus to maximum performance. The light detector is so sensitive that it can detect a single photon per day. The precision of the system of mirrors for the light is also record-breaking: the distance between the mirrors must remain constant to within a fraction of an atomic diameter relative to the wavelength of the laser.

World's most sensitive model-independent experiment starts searching for dark matter, Deutsches Elektronen-Synchrotron,

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Nano Sanitizer...


The disinfectant powder is stirred in bacteria-contaminated water (upper left). The mixture is exposed to sunlight, which rapidly kills all the bacteria (upper right). A magnet collects the metallic powder after disinfection (lower right). The powder is then reloaded into another beaker of contaminated water, and the disinfection process is repeated (lower left). (Image credit: Tong Wu/Stanford University)

Topics: Biology, Chemistry, Environment, Materials Science, Nanotechnology

When exposed to sunlight, a low-cost, recyclable powder can kill thousands of waterborne bacteria per second. Stanford and SLAC scientists say the ultrafast disinfectant could be a revolutionary advance for 2 billion people worldwide without access to safe drinking water.

At least 2 billion people worldwide routinely drink water contaminated with disease-causing microbes.

Now, scientists at Stanford University and SLAC National Accelerator Laboratory have invented a low-cost, recyclable powder that kills thousands of waterborne bacteria per second when exposed to ordinary sunlight. According to the Stanford and SLAC team, the discovery of this ultrafast disinfectant could be a significant advance for nearly 30 percent of the world’s population with no access to safe drinking water. Their results are published in a May 18 study in Nature Water.

“Waterborne diseases are responsible for 2 million deaths annually, the majority in children under the age of 5,” said study co-lead author Tong Wu, a former postdoctoral scholar of materials science and engineering (MSE) at the Stanford School of Engineering. “We believe that our novel technology will facilitate revolutionary changes in water disinfection and inspire more innovations in this exciting interdisciplinary field.”

Conventional water-treatment technologies include chemicals, which can produce toxic byproducts, and ultraviolet light, which takes a relatively long time to disinfect and requires a source of electricity.

The new disinfectant developed at Stanford is a harmless metallic powder that works by absorbing both UV and high-energy visible light from the sun. The powder consists of nano-size flakes of aluminum oxide, molybdenum sulfide, copper, and iron oxide.

“We only used a tiny amount of these materials,” said senior author Yi Cui, the Fortinet Founders Professor of MSE and of Energy Science & Engineering in the Stanford Doerr School of Sustainability. “The materials are low cost and fairly abundant. The key innovation is that, when immersed in water, they all function together.”

New nontoxic powder uses sunlight to quickly disinfect contaminated drinking water, Mark Shwartz, Stanford News.

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Balsa Chips...


Modified wood modulates electrical current: researchers at Linköping University and colleagues from the KTH Royal Institute of Technology have developed the world’s first electrical transistor made of wood. (Courtesy: Thor Balkhed)

Topics: Applied Physics, Biomimetics, Electrical Engineering, Materials Science, Research

Researchers in Sweden have built a transistor out of a plank of wood by incorporating electrically conducting polymers throughout the material to retain space for an ionically conductive electrolyte. The new technique makes it possible, in principle, to use wood as a template for numerous electronic components, though the Linköping University team acknowledges that wood-based devices cannot compete with traditional circuitry on speed or size.

Led by Isak Engquist of Linköping’s Laboratory for Organic Electronics, the researchers began by removing the lignin from a plank of balsa wood (chosen because it is grainless and evenly structured) using a NaClO2 chemical and heat treatment. Since lignin typically constitutes 25% of wood, removing it creates considerable scope for incorporating new materials into the structure that remains.

The researchers then placed the delignified wood in a water-based dispersion of an electrically conducting polymer called poly(3,4-ethylene-dioxythiophene)–polystyrene sulfonate, or PEDOT: PSS. Once this polymer diffuses into the wood, the previously insulating material becomes a conductor with an electrical conductivity of up to 69 Siemens per meter – a phenomenon the researchers attribute to the formation of PEDOT: PSS microstructures inside the 3D wooden “scaffold.”

Next, Engquist and colleagues constructed a transistor using one piece of this treated balsa wood as a channel and additional pieces on either side to form a double transistor gate. They also soaked the interface between the gates and channels in an ion-conducting gel. In this arrangement, known as an organic electrochemical transistor (OECT), applying a voltage to the gate(s) triggers an electrochemical reaction in the channel that makes the PEDOT molecules non-conducting and therefore switches the transistor off.

A transistor made from wood, Isabelle Dumé, Physics World

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A Charge for all Seasons...


The new composition for fluorine-containing electrolytes promises to maintain high battery charging performance for future electric vehicles even at sub-zero temperatures. (Image by Shutterstock.)

Topics: Battery, Chemistry, Climate Change, Global Warming, Lithium, Materials Science

Scientists developed a new and safer electrolyte for lithium-ion batteries that work as well in sub-zero conditions as it does at room temperature.

Many owners of electric vehicles worry about how effective their batteries will be in very cold weather. Now new battery chemistry may have solved that problem.

In current lithium-ion batteries, the main problem lies in the liquid electrolyte. This key battery component transfers charge-carrying particles called ions between the battery’s two electrodes, causing the battery to charge and discharge. But the liquid begins to freeze at sub-zero temperatures. This condition severely limits the effectiveness of charging electric vehicles in cold regions and seasons.

To address that problem, a team of scientists from the U.S. Department of Energy’s (DOE) Argonne and Lawrence Berkeley national laboratories developed a fluorine-containing electrolyte that performs well even in sub-zero temperatures.

“Our research thus demonstrated how to tailor the atomic structure of electrolyte solvents to design new electrolytes for sub-zero temperatures.” — John Zhang, Argonne group leader.

“Our team not only found an antifreeze electrolyte whose charging performance does not decline at minus 4 degrees Fahrenheit, but we also discovered, at the atomic level, what makes it so effective,” said Zhengcheng ​“John” Zhang, a senior chemist and group leader in Argonne’s Chemical Sciences and Engineering division.

This low-temperature electrolyte shows promise of working for batteries in electric vehicles, as well as in energy storage for electric grids and consumer electronics like computers and phones.

An electric vehicle battery for all seasons, Joseph E. Harmon, Argonne National Labs

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Fractals are a never-ending pattern that you can zoom in on, and the image doesn’t change. Fractals can occur in two dimensions, like frost on a window, or in three dimensions, like tree limbs. A recent discovery from Purdue University researchers has established that superconducting images, seen above in red and blue, are actually fractals that fill a three-dimensional space and are disorder driven rather than driven by quantum fluctuations as expected. Frost and tree images by Adobe. Superconducting image (center) from "Critical nematic correlations throughout the superconducting doping range in Bi2-xPbzSr2-yLayCuO6+x" in Nature Communications. Credit: Nature Communications (2023). DOI: 10.1038/s41467-023-38249-3

Topics: Applied Physics, Civilization, Computer Modeling, Condensed Matter Physics, Materials Science, Solid-State Physics, Superconductors

Meeting the world's energy demands is reaching a critical point. Powering the technological age has caused issues globally. It is increasingly important to create superconductors that can operate at ambient pressure and temperature. This would go a long way toward solving the energy crisis.

Advancements with superconductivity hinge on advances in quantum materials. When electrons inside quantum materials undergo a phase transition, the electrons can form intricate patterns, such as fractals. A fractal is a never-ending pattern. When zooming in on a fractal, the image looks the same. Commonly seen fractals can be a tree or frost on a windowpane in winter. Fractals can form in two dimensions, like the frost on a window, or in three-dimensional space, like the limbs of a tree.

Dr. Erica Carlson, a 150th Anniversary Professor of Physics and Astronomy at Purdue University, led a team that developed theoretical techniques for characterizing the fractal shapes that these electrons make in order to uncover the underlying physics driving the patterns.

Carlson, a theoretical physicist, has evaluated high-resolution images of the locations of electrons in the superconductor Bi2-xPbzSr2-yLayCuO6+x (BSCO) and determined that these images are indeed fractal and discovered that they extend into the full three-dimensional space occupied by the material, like a tree filling space.

What was once thought of as random dispersions within the fractal images are purposeful and, shockingly, not due to an underlying quantum phase transition as expected but due to a disorder-driven phase transition.

Carlson led a collaborative team of researchers across multiple institutions and published their findings, titled "Critical nematic correlations throughout the superconducting doping range in Bi2-xPbzSr2-yLayCuO6+x," in Nature Communications.

The team includes Purdue scientists and partner institutions. From Purdue, the team includes Carlson, Dr. Forrest Simmons, a recent Ph.D. student, and former Ph.D. students Dr. Shuo Liu and Dr. Benjamin Phillabaum. The Purdue team completed their work within the Purdue Quantum Science and Engineering Institute (PQSEI). The team from partner institutions includes Dr. Jennifer Hoffman, Dr. Can-Li Song, Dr. Elizabeth Main of Harvard University, Dr. Karin Dahmen of the University of Illinois at Urbana-Champaign, and Dr. Eric Hudson of Pennsylvania State University.

Researchers discover superconductive images are actually 3D and disorder-driven fractals, Cheryl Pierce, Purdue University,

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The new self-powered thermoelectric generator device uses an ultra-broadband solar absorber (UBSA) to capture sunlight, which heats the generator. Simultaneously, another component called a planar radiative cooling emitter (RCE) cools part of the device by releasing heat. Credit: Haoyuan Cai, Jimei University

Topics: Alternate Energy, Battery, Chemistry, Energy, Materials Science, Thermodynamics

Researchers have developed a new thermoelectric generator (TEG) that can continuously generate electricity using heat from the sun and a radiative element that releases heat into the air. Because it works during the day or night and in cloudy conditions, the new self-powered TEG could provide a reliable power source for small electronic devices such as outdoor sensors.

"Traditional power sources like batteries are limited in capacity and require regular replacement or recharging, which can be inconvenient and unsustainable," said research team leader Jing Liu from Jimei University in China. "Our new TEG design could offer a sustainable and continuous energy solution for small devices, addressing the constraints of traditional power sources like batteries."

TEGs are solid-state devices that use temperature differences to generate electricity without moving parts. In the journal Optics Express, Liu and a multi-institutional team of researchers describe and demonstrate a new TEG that can simultaneously generate the heat and cold necessary to create a temperature difference large enough to generate electricity even when the sun isn't out. The passive power source is made of components that can easily be manufactured.

"The unique design of our self-powered thermoelectric generator allows it to work continuously, no matter the weather," said Liu. "With further development, our TEG has the potential to impact a wide range of applications, from remote sensors to wearable electronics, promoting a more sustainable and eco-friendly approach to powering our daily lives."

New passive device continuously generates electricity during the day or night, Optica/Tech Explore

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Strange Metals II...


Credit: CC0 Public Domain

Topics: Applied Physics, Chemistry, Materials Science, Metamaterials, Quantum Mechanics

The behavior of so-called "strange metals" has long puzzled scientists—but a group of researchers at the University of Toronto may be one step closer to understanding these materials.

Electrons are discrete, subatomic particles that flow through wires like molecules of water flowing through a pipe. The flow is known as electricity, and it is harnessed to power and control everything from lightbulbs to the Large Hadron Collider.

In quantum matter, by contrast, electrons don't behave as they do in normal materials. They are much stronger, and the four fundamental properties of electrons—charge, spin, orbit, and lattice—become intertwined, resulting in complex states of matter.

"In quantum matter, electrons shed their particle-like character and exhibit strange collective behavior," says condensed matter physicist Arun Paramekanti, a professor in the U of T's Department of Physics in the Faculty of Arts & Science. "These materials are known as non-Fermi liquids, in which the simple rules break down."

Now, three researchers from the university's Department of Physics and Centre for Quantum Information & Quantum Control (CQIQC) have developed a theoretical model describing the interactions between subatomic particles in non-Fermi liquids. The framework expands on existing models and will help researchers understand the behavior of these "strange metals."

Their research was published in the journal Proceedings of the National Academy of Sciences (PNAS). The lead author is physics Ph.D. student Andrew Hardy, with co-authors Paramekanti and post-doctoral researcher Arijit Haldar.

"We know that the flow of a complex fluid like blood through arteries is much harder to understand than water through pipes," says Paramekanti. "Similarly, the flow of electrons in non-Fermi liquids is much harder to study than that in simple metals."

Hardy adds, "What we've done is construct a model, a tool, to study non-Fermi liquid behavior. And specifically, to deal with what happens when there is symmetry breaking, when there is a phase transition into a new type of system."

"Symmetry breaking" is the term used to describe a fundamental process found in all of nature. Symmetry breaks when a system—whether a droplet of water or the entire universe—loses its symmetry and homogeneity and becomes more complex.

Researchers develop new insight into the enigmatic realm of 'strange metals', Chris Sasaki, University of Toronto,

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Caveat Modifier...


The Biofire Smart Gun. Photographer: James Stukenberg for Bloomberg Businessweek

Topics: Biometrics, Biotechnology, Computer Science, Democracy, Materials Science, Semiconductor Technology

Tech Target (Alyssa Provazza, Editorial Director): "A smartphone is a cellular telephone with an integrated computer and other features not originally associated with telephones, such as an operating system, web browsing, and the ability to run software applications." Smartphones, however, have had a detrimental effect on humans regarding health, critical thinking, and cognitive skills, convenient though they are.

I've seen the idea of "smart guns" for decades. Like the fingerprint scan for biometric safes, it's a safeguard that some will opt for but most likely won't unless compelled by legislation, which in the current "thoughts and prayers" environment (i.e., sloganeering is easier than proposing a law if you continually get away with it), I'm not holding my breath. A recent, late 20th Century example:

In 1974, the federal government passed the National Maximum Speed Law, which restricted the maximum permissible vehicle speed limit to 55 miles per hour (mph) on all interstate roads in the United States.1 The law was a response to the 1973 oil embargo, and its intent was to reduce fuel consumption. In the year after the National Maximum Speed Law was enacted, road fatalities declined 16.4%, from 54,052 in 1973 to 45,196 in 1974.2

In April of 1987, Congress passed the Surface Transportation and Uniform Relocation Assistance Act, which permitted states to raise the legal speed limit on rural interstates to 65 mph.3 Under this legislation, 41 states raised their posted speed limits to 65 mph on segments of rural interstates. On November 28, 1995, Congress passed the National Highway Designation Act, which officially removed all federal speed limit controls. Since 1995, all US states have raised their posted speed limits on rural interstates; many have also raised the posted speed limits on urban interstates and non interstate roads.

Conclusions. Reduced speed limits and improved enforcement with speed camera networks could immediately reduce speeds and save lives, in addition to reducing gas consumption, cutting emissions of air pollutants, saving valuable years of productivity, and reducing the cost of motor vehicle crashes.

Long-Term Effects of Repealing the National Maximum Speed Limit in the United States, Lee S. Friedman, Ph.D., corresponding author Donald Hedeker, Ph.D., and Elihu D. Richter, MD, MPH, National Library of Medicine, National Institutes of Health

Homo Sapiens, (Latin) "wise men," don't always do smart things.

In an office parking lot about halfway between Denver and Boulder, a former 50-foot-long shipping container has been converted into a cramped indoor shooting range. Paper targets with torsos printed on them hang from two parallel tracks, and a rubber trap waits at the back of the container to catch the spent bullets. Black acoustic foam padding on the walls softens the gunshot noise to make the experience more bearable for the shooter, while an air filtration system sucks particulates out of the air. It’s a far cry from the gleaming labs of the average James Bond movie, but Q might still be proud.

The weapons being tested at this site are smart guns: They can identify their registered users and won’t fire [for] anyone else. Smart guns have been a notoriously quixotic category for decades. The weapons carry the hope that an extra technological safeguard might prevent a wide range of gun-related accidents and deaths. But making a smart gun that’s good enough to be taken seriously has proved beyond difficult. It’s rare to find engineers with a strong understanding of both ballistics and biometrics whose products can be expected to work perfectly in life-or-death situations.

Some recent attempts have amounted to little more than a sensor or two slapped onto an existing weapon. More promising products have required too many steps and taken too much time to fire compared with the speed of a conventional handgun. What separates the Biofire Smart Gun here in the converted shipping container is that its ID systems, which scan fingerprints and faces, have been thoroughly melded into the firing mechanism. The battery-powered weapon has the sophistication of high-end consumer electronics, but it’s still a gun at its core.

A Smart Gun Is Finally Here, But Does Anyone Want It? Ashlee Vance, Bloomberg Business Week

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Catalysis and Energy Savings…


Credit: Pixabay/CC0 Public Domain

Topics: Chemistry, Computer Modeling, Environment, Materials Science

In an advance, they consider a breakthrough in computational chemistry research. University of Wisconsin–Madison chemical engineers have developed a model of how catalytic reactions work at the atomic scale. This understanding could allow engineers and chemists to develop more efficient catalysts and tune industrial processes—potentially with enormous energy savings, given that 90% of the products we encounter in our lives are produced, at least partially, via catalysis.

Catalyst materials accelerate chemical reactions without undergoing changes themselves. They are critical for refining petroleum products and for manufacturing pharmaceuticals, plastics, food additives, fertilizers, green fuels, industrial chemicals, and much more.

Scientists and engineers have spent decades fine-tuning catalytic reactions—yet because it's currently impossible to directly observe those reactions at the extreme temperatures and pressures often involved in industrial-scale catalysis, they haven't known exactly what is taking place on the nano and atomic scales. This new research helps unravel that mystery with potentially major ramifications for the industry.

In fact, just three catalytic reactions—steam-methane reforming to produce hydrogen, ammonia synthesis to produce fertilizer, and methanol synthesis—use close to 10% of the world's energy.

"If you decrease the temperatures at which you have to run these reactions by only a few degrees, there will be an enormous decrease in the energy demand that we face as humanity today," says Manos Mavrikakis, a professor of chemical and biological engineering at UW–Madison who led the research. "By decreasing the energy needed to run all these processes, you are also decreasing their environmental footprint."

New atomic-scale understanding of catalysis could unlock massive energy savings, Jason Daley, University of Madison-Wisconson

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Caveat Super...


A diamond anvil is used to put superconducting materials under high pressure. Credit: J. Adam Fenster/University of Rochester

Topics: Applied Physics, Condensed Matter Physics, Materials Science, Superconductors

Will a possible breakthrough for room-temperature superconducting materials hold up to scrutiny?

This week researchers claimed to have discovered a superconducting material that can shuttle electricity with no loss of energy under near-real-world conditions. But drama and controversy behind the scenes have many worried that the breakthrough may not hold up to scientific scrutiny.

“If you were to find a room-temperature, room-pressure superconductor, you’d have a completely new host of technologies that would occur—that we haven’t even begun to dream about,” says Eva Zurek, a computational chemist at the University at Buffalo, who was not involved in the new study. “This could be a real game changer if it turns out to be correct.”

Scientists have been studying superconductors for more than a century. By carrying electricity without shedding energy in the form of heat, these materials could make it possible to create incredibly efficient power lines and electronics that never overheat. Superconductors also repel magnetic fields. This property lets researchers levitate magnets over a superconducting material as a fun experiment—and it could also lead to more efficient high-speed maglev trains. Additionally, these materials could produce super strong magnets for use in wind turbines, portable magnetic resonance imaging machines, or even nuclear fusion power plants.

The only superconducting materials previously discovered require extreme conditions to function, which makes them impractical for many real-world applications. The first known superconductors had to be cooled with liquid helium to temperatures only a few degrees above absolute zero. In the 1980s, researchers found superconductivity in a category of materials called cuprates, which work at higher temperatures yet still require cooling with liquid nitrogen. Since 2015 scientists have measured room-temperature superconductive behavior in hydrogen-rich materials called hydrides. but they have to be pressed in a sophisticated viselike instrument called a diamond anvil cell until they reach a pressure of about a quarter to half of that found near the center of Earth.

The new material, called nitrogen-doped lutetium hydride, is a blend of hydrogen, the rare-earth metal lutetium, and nitrogen. Although this material also relies on a diamond anvil cell, the study found that it begins exhibiting superconductive behavior at a pressure of about 10,000 atmospheres—roughly 100 times lower than the pressures that other hydrides require. The new material is “much closer to ambient pressure than previous materials,” says David Ceperley, a condensed matter physicist at the University of Illinois at Urbana-Champaign, who was not involved in the new study. He also notes that the material remains stable when stored at a room pressure of one atmosphere. “Previous stuff was only stable at a million atmospheres, so you couldn’t really take it out of the diamond anvil” cell, he says. “The fact that it’s stable at one atmosphere of pressure also means that it’d be easier to manufacture.”

Controversy Surrounds Blockbuster Superconductivity Claim, Sophie Bushwick, Scientific American

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Chips for America...


Topics: Economics, Electrical Engineering, Materials Science, Semiconductor Technology

WASHINGTON — The Biden-Harris administration, through the U.S. Department of Commerce’s National Institute of Standards and Technology, today launched the first CHIPS for America funding opportunity for manufacturing incentives to restore U.S. leadership in semiconductor manufacturing, support good-paying jobs across the semiconductor supply chain, and advance U.S. economic and national security.

As part of the bipartisan CHIPS and Science Act, the Department of Commerce oversees $50 billion to revitalize the U.S. semiconductor industry, including $39 billion in semiconductor incentives. The first funding opportunity seeks applications for projects to construct, expand or modernize commercial facilities for the production of leading-edge, current-generation, and mature-node semiconductors. This includes both front-end wafer fabrication and back-end packaging. The department will also release a funding opportunity for semiconductor materials and equipment facilities in the late spring and one for research and development facilities in the fall.

“The CHIPS and Science Act presents a historic opportunity to unleash the next generation of American innovation, protect our national security and preserve our global economic competitiveness,” said Secretary of Commerce Gina M. Raimondo. “When we have finished implementing CHIPS for America, we will be the premier destination in the world where new leading-edge chip architectures can be invented in our research labs, designed for every end-use application, manufactured at scale, and packaged with the most advanced technologies. Throughout our work, we are committed to protecting taxpayer dollars, strengthening America’s workforce, and giving America’s businesses a platform to do what they do best: innovate, scale, and compete.”

The CHIPS and Science Act is part of President Joe Biden’s economic plan to invest in America, stimulating private sector investment, creating good-paying jobs, making more in the United States, and revitalizing communities left behind. 

CHIPS for America also today released a “Vision for Success,” laying out strategic objectives building on the vision Secretary Raimondo shared in her speech last week at Georgetown University’s School of Foreign Service. To advance U.S. economic and national security, the department aims to reach the following goals by the end of the decade: (1) make the U.S. home to at least two new large-scale clusters of leading-edge logic chip fabs, (2) make the U.S. home to multiple high-volume advanced packaging facilities, (3) produce high-volume leading-edge memory chips, and (4) increase production capacity for current-generation and mature-node chips, especially for critical domestic industries. Read more about these goals in the Vision for Success paper here.

NIST: Biden-Harris Administration Launches First CHIPS for America Funding Opportunity

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Scanning With a Twist...


How it works: illustration of the quantum twisting microscope in action. Electrons tunnel from the probe (inverted pyramid at the top) to the sample (bottom) in several places at once (green vertical lines) in a quantum-coherent manner. (Courtesy: Weizmann Institute of Science)

Topics: Chemistry, Entanglement, Materials Science, Nanotechnology, Quantum Mechanics

When the scanning tunneling microscope debuted in the 1980s, the result was an explosion in nanotechnology and quantum-device research. Since then, other types of scanning probe microscopes have been developed, and together they have helped researchers flesh out theories of electron transport. But these techniques probe electrons at a single point, thereby observing them as particles and only seeing their wave nature indirectly. Now, researchers at the Weizmann Institute of Science in Israel have built a new scanning probe – the quantum twisting microscope – that detects the quantum wave characteristics of electrons directly.

“It’s effectively a scanning probe tip with an interferometer at its apex,” says Shahal Ilani, the team leader. The researchers overlay a scanning probe tip with ultrathin graphite, hexagonal boron nitride, and a van der Waals crystal such as graphene, which conveniently flopped over the tip like a tent with a flat top about 200 nm across. The flat end is key to the device’s interferometer function.  Instead of an electron tunneling between one point in the sample and the tip, the electron wave function can tunnel across multiple points simultaneously.

“Quite surprisingly, we found that the flat end naturally pivots so that it is always parallel with the sample,” says John Birkbeck, the corresponding author of a paper describing this work. This is fortunate because any tilt would alter the tunneling distance and hence strength from one side of the plateau to the other. “It is the interference of these tunneling paths, as identified in the measured current, that gives the device its unique quantum-wave probing function,” says Birkbeck.

Scanning probe with a twist observes the electron’s wavelike behavior, Anna Demming, Physics World

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Like Mushrooms for Plastics...


Credit: VTT Technical Research Centre of Finland

Topics: Biology, Biotechnology, Chemistry, Materials Science, Mechanical Engineering

A research group from VTT Technical Research Center of Finland has unlocked the secret behind the extraordinary mechanical properties and ultra-light weight of certain fungi. The complex architectural design of mushrooms could be mimicked and used to create new materials to replace plastics. The research results were published on February 22, 2023, in Science Advances.

VTT's research shows for the first time the complex structural, chemical, and mechanical features adapted throughout the course of evolution by Hoof mushroom (Fomes fomentarius). These features interplay synergistically to create a completely new class of high-performance materials.

Research findings can be used as a source of inspiration to grow from the bottom up the next generation of mechanically robust and lightweight, sustainable materials for various applications under laboratory conditions. These include impact-resistant implants, sports equipment, body armor, and exoskeletons for aircraft, electronics, or windshield surface coatings.

Mushrooms could help replace plastics in new high-performance ultra-light materials, VTT Technical Research Centre of Finland,

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When Water Outpaces Silicon…


On target: Water is fanned out through a specially developed nozzle, and then a laser pulse is passed through it to create a switch. (Courtesy: Adrian Buchmann)

Topics: Applied Physics, Lasers, Materials Science, Photonics, Semiconductor Technology

A laser-controlled water-based switch that operates twice as fast as existing semiconductor switches has been developed by a trio of physicists in Germany. Adrian Buchmann, Claudius Hoberg, and Fabio Novelli at Ruhr University Bochum used an ultrashort laser pulse to create a temporary metal-like state in a jet of liquid water. This altered the transmission of terahertz pulses over timescales of just tens of femtoseconds.

With the latest semiconductor-based switches approaching fundamental upper limits on how fast they can operate, researchers are searching for faster ways of switching signals. One unexpected place to look for inspiration is the curious behavior of water under extreme conditions – like those deep within ice-giant planets or created by powerful lasers.

Molecular dynamics simulations suggest water enters a metallic state at pressures of 300 GPa and temperatures of 7000 K. While such conditions do not occur on Earth, it is possible that this state contributes to the magnetic fields of Uranus and Neptune. To study this effect closer to home, recent experiments have used powerful, ultrashort laser pulses to trigger photo-ionization in water-based solutions – creating fleeting, metal-like states.

Water-based switch outpaces semiconductor devices, described in APL Photonics.

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Credit: Nicoletta Barolini

Topics: Chemistry, Graphene, Materials Science, Modern Physics, Nanotechnology

Graphullerene, an atom-thin material made of linked fullerene subunits, gives scientists a new form of modular carbon to play with.

Carbon, in its myriad forms, has long captivated the scientific community. Besides being the primary component of all organic life on earth, material forms of carbon have earned their fair share of breakthroughs. In 1996, the Nobel Prize in Chemistry went to the discoverers of fullerene, a superatomic symmetrical structure of 60 carbon atoms shaped like a soccer ball; in 2010, researchers working with an ultra-strong, atom-thin version of carbon, known as graphene, won the Nobel Prize in Physics.

Today in work published in Nature, researchers led by Columbia chemists Xavier Roy, Colin Nuckolls, and Michael Steigerwald, with postdoc and first author Elena Meirzadeh have discovered a new version of carbon that sits somewhere in between fullerene and graphene: graphullerene. It’s a new two-dimensional form of carbon made up of layers of linked fullerenes peeled into ultrathin flakes from a larger graphullerite crystal—just like how graphene is peeled from graphite crystals (the same material found in pencils).

“It is amazing to find a new form of carbon,” said Nuckolls. “It also makes you realize that there is a whole family of materials that can be made in a similar way that will have new and unusual properties as a consequence of the information written into the superatomic building blocks.”

Columbia Chemists Discover a New Form of Carbon: Graphene’s “Superatomic” Cousin, Ellen Neff,

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Serendipitous Quasicrystals...


Cross-section of a fulgurite sample showing fused sand and melted conductor metal from a downed powerline. Credit: Luca Bindi et al.

Topics: Condensed Matter Physics, Energy, Materials Science

A team of researchers from Università di Firenze, the University of South Florida, California Institute of Technology, and Princeton University has found an incidence of a quasicrystal formed during an accidental electrical discharge.

In their paper published in Proceedings of the National Academy of Sciences, the group describes their study of a quasicrystal found in a sand dune in Nebraska.

Quasicrystals, as their name suggests, are crystal-like substances. They possess characteristics not found in ordinary crystals, such as a non-repeating arrangement of atoms. To date, quasicrystals have been found embedded in meteorites and in the debris from nuclear blasts. In this new effort, the researchers found one embedded in a sand dune in Sand Hills, Nebraska.

A study of the quasicrystal showed it had 12-fold, or dodecagonal, symmetry—something rarely seen in quasicrystals. Curious about how it might have formed and ended up in the sand dune, the researchers did some investigating. They discovered that a power line had fallen on the dune, likely due to a lightning strike. They suggest the electrical surge from either the power line or the lightning could have produced the quasicrystal.

The researchers note that the quasicrystal was found inside a tubular piece of fulgurite. They suggest it was also formed during the electrical surge due to the fusing of melted sand and metal from the power line.

Quasicrystal formed during accidental electrical discharge, Bob Yirka,

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Pushing Beyond Moore...


Clean-room technicians at the AIM Photonics NanoTech chip fabrication facility in Albany, New York.  Credit: SUNY Polytechnic Institute

Topics: Computer Science, Electrical Engineering, Materials Science, Nanotechnology, Semiconductor Technology

Over 50 Years of Moore's Law - Intel

GAITHERSBURG, Md. — The U.S. Department of Commerce’s National Institute of Standards and Technology (NIST) has entered into a cooperative research and development agreement with AIM Photonics that will give chip developers a critical new tool for designing faster chips that use both optical and electrical signals to transmit information. Called integrated photonic circuits, these chips are key components in fiber-optic networks and high-performance computing facilities. They are used in laser-guided missiles, medical sensors, and other advanced technologies. 

AIM Photonics, a Manufacturing USA institute, is a public-private partnership that accelerates the commercialization of new technologies for manufacturing photonic chips. The New York-based institute provides small and medium-sized businesses, academics, and government researchers access to expertise and fabrication facilities during all phases of the photonics development cycle, from design to fabrication and packaging.

NIST and AIM Photonics Team Up on High-Frequency Optical/Electronic Chips

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Topics: Alternate Energy, Applied Physics, Chemistry, Materials Science, Solar Power

As ultrathin organic solar cells hit new efficiency records, researchers see green energy potential in surprising places.

In November 2021, while the municipal utility in Marburg, Germany, was performing scheduled maintenance on a hot water storage facility, engineers glued 18 solar panels to the outside of the main 10-meter-high cylindrical tank. It’s not the typical home for solar panels, most of which are flat, rigid silicon and glass rectangles arrayed on rooftops or in solar parks. The Marburg facility’s panels, by contrast, are ultrathin organic films made by Heliatek, a German solar company. In the past few years, Heliatek has mounted its flexible panels on the sides of office towers, the curved roofs of bus stops, and even the cylindrical shaft of an 80-meter-tall windmill. The goal: expanding solar power’s reach beyond flat land. “There is a huge market where classical photovoltaics do not work,” says Jan Birnstock, Heliatek’s chief technical officer.

Organic photovoltaics (OPVs) such as Heliatek’s are more than 10 times lighter than silicon panels and in some cases cost just half as much to produce. Some are even transparent, which has architects envisioning solar panels, not just on rooftops, but incorporated into building facades, windows, and even indoor spaces. “We want to change every building into an electricity-generating building,” Birnstock says.

Heliatek’s panels are among the few OPVs in practical use, and they convert about 9% of the energy in sunlight to electricity. But in recent years, researchers around the globe have come up with new materials and designs that, in small, lab-made prototypes, have reached efficiencies of nearly 20%, approaching silicon and alternative inorganic thin-film solar cells, such as those made from a mix of copper, indium, gallium, and selenium (CIGS). Unlike silicon crystals and CIGS, where researchers are mostly limited to the few chemical options nature gives them, OPVs allow them to tweak bonds, rearrange atoms, and mix in elements from across the periodic table. Those changes represent knobs chemists can adjust to improve their materials’ ability to absorb sunlight, conduct charges, and resist degradation. OPVs still fall short of those measures. But, “There is an enormous white space for exploration,” says Stephen Forrest, an OPV chemist at the University of Michigan, Ann Arbor.

Solar Energy Gets Flexible, Robert F. Service, Science Magazine

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Solar Lilly Pads...


A floating artificial leaf – which generates clean fuel from sunlight and water – on the River Cam near King's College Chapel in Cambridge, UK. (Courtesy: Virgil Andrei)

Topics: Climate Change, Energy, Environment, Materials Science, Solar Power

Leaf-like devices that are light enough to float on water could be used to generate fuel from solar farms located on open water sources. This avenue hasn’t been explored before, according to researchers from the University of Cambridge in the UK who developed them. The new devices are made from thin, flexible substrates and perovskite-based light-absorbing layers. Tests showed that they can produce either hydrogen or syngas (a mixture of hydrogen and carbon monoxide) while floating on the River Cam.

Artificial leaves like these are a type of photoelectrochemical cell (PEC) that transforms sunlight into electrical energy or fuel by mimicking some aspects of photosynthesis, such as splitting water into its constituent oxygen and hydrogen. This differs from conventional photovoltaic cells, which convert light directly into electricity.

Because PEC artificial leaves contain both light harvesting and catalysis components in one compact device, they could, in principle, be used to produce fuel from sunlight cheaply and simply. The problem is that current techniques for making them can’t be scaled up. What is more, they are often composed of fragile and heavy bulk materials, which limits their use.

In 2019 a team of researchers led by Erwin Reisner developed an artificial leaf that produced syngas from sunlight, carbon dioxide, and water. This device contained two light absorbers and catalysts, but it also incorporated a thick glass substrate and coatings to protect against moisture, which made it cumbersome.

Floating artificial leaves could produce solar-generated fuel, Isabelle Dumé, Physics World

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Solid-State Cooling...


Cool stuff: the diagram shows how the temperature of the caloric material was measured. The plot in the center shows the temperature change in the sample when exposed to a magnetic field. The plot on the right shows the change in temperature when the sample is strained. (Courtesy: Peng Wu et al/Acta Materialia 237 118154)

Topics: Global Warming, Green Tech, Materials Science, Solid-State Physics, Thermodynamics

Researchers in China have shown that applying strain to a composite material using an electric field induces a large and reversible caloric effect. This novel way of enhancing the caloric effect without a magnetic field could open new avenues of solid-state cooling and lead to more energy-efficient and lighter refrigerators.

The International Institute of Refrigeration estimates that 20% of all electricity used globally is expended on vapor-compression refrigeration – which is the technology used in conventional refrigerators and air conditioners. What is more, the refrigerants used in these systems are powerful greenhouse gases that contribute significantly to global warming. As a result, scientists are trying to develop more environmentally friendly refrigeration systems.

Cooling systems can also be made from completely solid-state systems, but these cannot currently compete with vapor compression for most mainstream applications. Today, most commercial solid-state cooling systems use the Peltier effect, which is a thermoelectric process that suffers from high cost and low efficiency.

Solid-state cooling is achieved via electric field-induced strain, Hardepinder Singh, Physics World

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