Scientists just watched a bizarre phase of matter turn into an even stranger one. For the first time, they saw a superfluid turn into a supersolid — a transition they weren't sure was even possible.

In a Jan. 28 study in the journal Nature, researchers observed a group of excitons — quasiparticles that combine an electron and an electron hole — transforming from a superfluid into a supersolid and back again. It is the first time excitons have been seen condensing into a supersolid, undergoing a reversible phase transition the way water can transform from a liquid to ice and back.

Secret phases of matter

There are many more phases of matter than the typical three we encounter every day (gases, liquids and solids), although most of these other matter states exist only under extreme conditions. Superfluids are one type that occurs only when some particles, like helium isotopes and excitons, are cooled to just above absolute zero — the complete absence of heat. They're not quite liquids — they flow without resistance from friction — and when stirred, they form tiny eternal tornadoes called quantum vortices.

Supersolids, on the other hand, are a state of matter theorized to exist when superfluids are cooled even more. They keep superfluidity's zero viscosity, but instead of particles moving around in a liquid-like blob, they form an orderly structure, like a crystal lattice, while maintaining their ability to flow and form quantum vortices.

Supersolids have been made in labs before, including in 2021, when researchers created 2D supersolid dysprosium and in 2024 when they saw quantum vortices in a supersolid. However, they achieved this only by using extra equipment and energy to force particles into an orderly lattice. The new study, by contrast, demonstrates a natural phase transition.

"For the first time, we've seen a superfluid undergo a phase transition to become what appears to be a supersolid," Cory Dean, a physicist at Columbia University and co-author of the study, said in a statement.

Exploring new boundaries

To do it, researchers put two pieces of graphene — which is like a very thin sheet of paper made entirely of carbon atoms — very close together. Then, they added a strong magnetic field and cooled the system to form an exciton "soup."

When cooled to between 2.7 and 7.2 degrees Fahrenheit (1.5 to 4 degrees Celsius) above absolute zero, the excitons formed a superfluid. When cooled more than that, the excitons changed into an electrically insulative mysterious new phase that the team suspects is the theorized supersolid state.

"Superfluidity is generally regarded as the low-temperature ground state," Jia Li, a physicist at the University of Texas at Austin and co-author of the study, said in the statement. "Observing an insulating phase that melts into a superfluid is unprecedented. This strongly suggests that the low-temperature phase is a highly unusual exciton solid."

The team is looking at other materials to test, as well as finding new ways to measure and study the exciton supersolid state.

"For now, we're exploring the boundaries around this insulating state, while building new tools to measure it directly," Dean said. Further study will help scientists understand how supersolids and superfluids behave, deepen our understanding of particle physics and work toward applications of higher-temperature supersolids.

Scientists have found a new way to manipulate graphene to create a substance with record-breaking energy and power density.

When incorporated into energy storage devices called supercapacitors, this new form of graphene could be the key to high-capacity, fast-charging energy storage that could deliver power more quickly than conventional batteries, the researchers said in a statement.

The new material, called multiscale reduced graphene oxide (M-rGO), is created from graphite, a globally abundant resource. Researchers incorporated it into pouch cells, a type of rechargeable battery packaged into a thin, flexible, laminated foil envelope instead of rigid metal. The scientists published their findings Sept. 15 in the journal Nature Communications.

Pouch cells are used in electric vehicles, drones, wearable electronics, laptops, smartphones and tablets. Building them from M-rGO could lead to improvements in total capacity, charge time and the ability to power more complex and power-hungry devices with smaller batteries, according to the research team.

Soaking up power

Whereas traditional batteries store energy in chemical bonds, supercapacitors are electrochemical capacitors that store energy as separated electric charge on electrode surfaces. They have the advantage of superior energy density — how much energy can be stored in a given space — and power density — how quickly energy can be delivered per unit volume — over traditional batteries.

Until now, however, supercapacitors have been hamstrung by one significant limitation: only a portion of the potential energy storage of the materials from which they were created was available for use.

This limitation comes from graphene's physical makeup. While it has the advantage of allowing for denser electrodes — the solid conductors in a battery where charge is stored — it's very inefficient at using that space. Simply stacking graphene, for instance, is inefficient because the sheets adhere too closely together and don't leave enough space for the ions that need to move in and out to store energy.

To get around this problem, scientists built messy 3D structures similar to sponges, which provide both large amounts of storage area and pathways for ions to move. While lightweight, the downside is that these structures were large and cumbersome.

This breakthrough overcomes that issue by heating the graphene in a two-step process. This results in a tangled, curved graphene network with multiple levels of structure that still allows for the rapid movement of ions while providing lots of surface area for energy storage.

"This discovery could allow us to build fast-charging supercapacitors that store enough energy to replace batteries in many applications, and deliver it far more quickly," said Mainak Majumder, a professor of mechanical and aerospace engineering at Australia's Monash University, in the statement.

Scientists have used a new technique to synthesize diamonds at normal, atmospheric pressure and without a starter gem, which could make the precious gemstones much easier to grow in the lab.     

Natural diamonds form in Earth's mantle, the molten zone buried hundreds of miles beneath the planet's surface. The process takes place under tremendous pressures of several gigapascals and scorching temperatures exceeding 2,700 degrees Fahrenheit (1,500 degrees Celsius).

Similar conditions are employed in the method currently used to synthesize 99% of all artificially created diamonds. Called high-pressure and high-temperature (HPHT) growth, this method uses these extreme settings to coax carbon dissolved in liquid metals, like iron, to convert it to diamond around a small seed, or starter diamond. 

However, the high pressures and temperatures are difficult to produce and maintain. Plus, the components involved affect the diamonds' size, with the largest being about a cubic centimeter, or about as big as a blueberry. Besides, HPHT takes a fairly long time — a week or two — to produce even these tiny gems. Another method, called chemical vapor deposition, eliminates some requirements of HPHT, like high pressures. But others persist, like the need for seeds.

The new technique eliminates some drawbacks of both synthesis processes. A team led by Rodney Ruoff, a physical chemist at the Institute for Basic Science in South Korea, published their findings April 24 in the journal Nature. 

Related: Scientists may have pinpointed the true origin of the Hope Diamond and other pristine gemstones

The diamond crucible

The novel method was a long time in the making. "For over a decade I have been thinking about new ways to grow diamonds, as I thought it might be possible to achieve this in what might be unexpected (per 'conventional' thinking) ways," Ruoff told Live Science by email.

To start out, the researchers used electrically heated gallium with a bit of silicon in a graphite crucible. Gallium may seem like an esoteric element, but it was selected because a previous, unrelated study showed that it could catalyze the formation of graphene from methane. Graphene, like diamond, is pure carbon, but it contains the atoms in one layer rather than in the gemstone's tetrahedral orientation. 

The researchers housed the crucible in a home-built chamber maintained at sea-level atmospheric pressure, through which superhot, carbon-rich methane gas could be flushed. Designed by co-author Won Kyung Seong, also of the Institute for Basic Science, this 2.4-gallon (9 liters) chamber could be readied for experimentation in just 15 minutes, allowing the team to rapidly undertake runs with different concentrations of metals and gases. 

Through such tweaking, the researchers figured that a gallium-nickel-iron mixture — coupled with a pinch of silicon — was optimal for catalyzing the growth of diamonds. Indeed, with this blend, the team obtained diamonds from the crucible's base after just 15 minutes. Within two and a half hours, a more complete diamond film formed. Spectroscopic analyses showed that this film was largely pure but contained a few silicon atoms.

The minutiae of the mechanism that formed the diamonds are still largely murky, but the researchers think a temperature drop drives carbon from the methane toward the crucible's center, where it coalesces into diamond. Plus, without silicon, no diamonds form, so the researchers think it may act as a seed for the carbon to crystallize around. 

However, the new method has its own challenges. One problem is that the diamonds grown with this technique are tiny; the largest ones are hundreds of thousands of times smaller than the ones grown with HPHT.  That makes them too small to be used as jewels.

Other potential uses — for example, in more technological applications like polishing and drilling — for the diamonds synthesized with the new technique are unclear. However, because the process involves low pressure, Ruoff said, it might significantly scale up diamond synthesis. 

"In about a year or two, the world might have a clearer picture of things like possible commercial impact," he added.  

Researchers have proven that a metallic alloy of chromium, cobalt and nickel is officially the toughest material on Earth — more than 100 times tougher than the wonder material graphene.

In a new study published Dec. 1 in the journal Science, researchers subjected the ultra-tough alloy to extremely cold temperatures, in order to test how fracture-resistant the material is. Scientists have known for years that this alloy is one tough cookie — however, to the team's surprise, the alloy only became tougher and more resistant to cracks as temperatures plummeted. 

This super-resistance to fracture is in stark contrast to most materials, which only become more brittle in freezing temperatures, according to the study authors.

"People talk about the toughness of graphene, and that is measured at just 4 megapascals per meter," study co-author Robert Ritchie, a professor of engineering at the University of California Berkeley and senior faculty scientist at the Lawrence Berkeley National Laboratory, told Live Science. "The toughness of aluminum alloys used in aircraft is 35 megapascals per meter. This material has a toughness of 450 to 500 megapascals per meter… these are mind-boggling numbers." 

The potential applications of such a tough material range from space infrastructure to fracture-resistant containers for clean energy uses here on Earth. However, Ritchie noted, two of the alloy's three elements (nickel and cobalt) are prohibitively expensive, limiting the alloy's usefulness to the laboratory for the foreseeable future.

Strange alloy

The chromium, cobalt and nickel alloy is an example of a high entropy alloy (HEA). Unlike most alloys, which are made predominantly of one element with lower amounts of additional elements added, HEAs are made of an equal mix of each constituent element. 

This HEA is extremely malleable, or ductile, meaning it can bend under pressure to withstand fracturing, according to the study authors. Several quirks of the alloy's molecular structure make it so extraordinarily malleable. One key mechanism, for example, causes atoms within the alloy to dislocate under pressure, allowing them to shear over one another. This, along with various other mechanisms, allow the material to keep deforming as pressure increases, without fracturing or breaking.

"Each one of these mechanisms kicks in at a later stage when you increase the strain on the material and that's the perfect recipe for high toughness," Ritchie added. "What is remarkable is these mechanisms get more effective in colder temperatures."

The researchers initially tested the alloy's toughness by exposing it to liquid nitrogen at temperatures of around minus 321 degrees Fahrenheit (minus 196 degrees Celsius). When the alloy's toughness only improved, the team wondered how much further they could push the material's limits. 

Dong Liu, a physicist at Bristol University in England, and colleagues designed an experiment to expose the alloy to liquid helium, which can cool to super-frigid temperatures of minus 424 F (minus 253 C). The team then watched neutrons scatter off the material in a process called neutron diffraction to peer into the structure of the alloy and see how cracks formed as pressure increased. 

The experiment showed that when it came to toughness, the alloy blew graphene out of the water.

"Graphene is very high strength, but it doesn't have any damage tolerance," Liu told Live Science. "It's very brittle and shatters just like a mug you throw on the floor that shatters into pieces." 

Another drawback of graphene is that its high strength only holds at exceptionally small, nanometer-level scales, Liu added. Meanwhile, the samples of chromium, cobalt and nickel alloy tested by Liu and her team were cigarette-pack-size, meaning the HEA maintained its toughness at the scale of everyday objects.

Materials of the future

While more testing is needed before this material can be practically applied, Liu is optimistic that the alloy could be used for many projects, both in space and on Earth. For example, the HEA could be used in hydrogen storage containers that could make environmentally friendly hydrogen-powered vehicles more feasible.

"If you drive a car with a hydrogen vessel made from something very brittle you're essentially carrying a bomb around with you,” Liu said. “But not with this material."

Ritchie, meanwhile, is cautious in suggesting potential applications of the alloy, as moving material from the lab to the "real world" requires a lot of knowledge and time, while the costs of nickel and cobalt remain prohibitively high. However, he is interested in developing recipes for new alloys that could be just as tough, using different elements.

"There's 50 usable elements in the periodic table," Ritchie said. "Taking combinations of three, five or seven of them means there are millions of new alloys."

Graphene, one of the world's strongest materials, isn't normally magnetic. But when stacked and twisted, graphene develops a rare form of magnetism, new research finds. 

The magnetic field isn't created by the usual spin of electrons within the individual graphene layers, but instead arises from the collective swirling of electrons in all of the three-layers of the stacked graphene structure, researchers reported Oct. 12 in the journal Nature Physics.

Graphene is a material made of a single layer (or monolayer) of carbon atoms arranged in a honeycomb pattern. It's incredibly light and strong (though it is vulnerable to cracking). It also conducts electricity, making it exciting for use in electronics and sensors. 

Related: Elementary, my dear: 8 little-known elements

"We wondered what would happen if we combined graphene monolayers and bilayers into a twisted three-layer system," Cory Dean, a physicist at Columbia University in New York and one of the senior authors on the new paper, said in a statement. "We found that varying the number of graphene layers endows these composite materials with some exciting new properties that had not been seen before."

Dean and his colleagues stacked two layers of graphene and then added a single layer on top, rotating the stack by 1 degree. They then studied this graphene sandwich in a variety of circumstances, including temperatures just above absolute zero (the point at which all molecular motion stops). At these low temperatures, they found that the graphene stopped conducting electricity and became an insulator instead.

They also found that they could control the properties of the twisty stack of graphene by applying an electric field. When the electric field was oriented in one direction, the system acted like a twisted double layer of graphene. When they reversed the field, the stack took on the properties of a twisted four-layer graphene structure.

Perhaps strangest of all was the rare magnetism that appeared in the three-layer structure. A study published by another group in the journal Advanced Materials found that graphene bonded with boron nitride can give rise to a strange magnetic field; that field arose from the molecular bonds of the carbon in graphene and the boron in boron nitride. The new research reveals that this same type of magnetism can occur in pure graphene alone, simply because of interactions between carbon molecules. 

"Pure carbon is not magnetic," study co-author Matthew Yankowitz, a physicist at the University of Washington in Seattle, said in the statement. "Remarkably, we can engineer this property by arranging our three graphene sheets at just the right twist angles." 

The structure also contains regions where the properties are undisturbed by the twisting of the layer. These unique areas in the material could be exploited for data storage or quantum computing applications, study co-author Xiaodong Xu, also at the University of Washington, said in the statement. 

The researchers are now planning to delve deeper into the fundamental properties of the graphene structure. "This is really just the beginning," Yankowitz said.

Originally published on Live Science.

Scientists have invented a new form of gold that could be incredibly handy for use in medical technology, but sadly, it won't make much of a statement on your ring finger. That's because this gold is only 2 atoms thick — roughly a million times thinner than a human fingernail.

The researchers who created it call the gold "nanoseaweed" for its greenish hue and jagged shape under the microscope. According to a study published today (Aug. 6) in the journal Advanced Science, this barely visible bling is the thinnest form of gold ever created — so thin, it's technically two-dimensional.

Why make something so shiny, so tiny? Much like the absurdly strong nanomaterial graphene, the power of this gold lies in its surface-area-to-volume ratio, providing ample surfaces for chemical reactions to occur on without any filler material in between the sheet's two sides. It makes for an incredibly efficient nanomaterial that, the researchers claim, has myriad possible applications in medical technology and electronics.

"Gold is a highly effective catalyst," study co-author Stephen Evans, head of the Molecular and Nanoscale Physics Group at the University of Leeds, said in a statement. "Because the nanosheets are so thin, just about every gold atom plays a part in the catalysis. It means the process is highly efficient."

The researchers made this shiny seaweed by combining a solution called methyl orange (a substance usually used as a pH indicator, but used here as a "confinement agent" to limit the growth of gold) with a cocktail of other chemicals, including watery mixtures of gold and sodium.

After the mixture was spun in a centrifuge, the gold separated out into lopsided leaves that were 2 atoms thick. Subsequent lab tests showed that these leaves were effective at speeding up chemical reactions, making them a viable replacement for the bulkier forms of gold nanoparticles used across technology and medicine today, the researchers wrote.

• Photos: Gold, Amber and Bronze Treasures Found in Iron Age Grave
• In Photos: Treasure Ship Holding Gold and Emeralds Discovered
• Gold Rush Shipwreck: Photos of a Real-Life Underwater Treasure Hunt

Originally published on Live Science.

The quest to engineer touch-sensitive "synthetic skin," which could one day help amputees feel pressure or contact on their prosthetic limbs, is a hot topic for researchers. But a problem plagues this engineering effort: how to provide an energy source for such skin so that it can send signals.

Now, one research team has a potential solution: They've made synthetic skin that can be powered by sunlight.

The new development is the first touch-sensitive synthetic skin with solar-powered cells integrated into the skin itself, said the study's principal investigator, Ravinder Dahiya, a professor of electronic and nanoscale engineering at the University of Glasgow in Scotland.

Dahiya and his team made the transparent skin out of four thin layers: solar cells on the bottom, followed by polyvinyl chloride (PVC, a thin synthetic plastic), a single layer of graphene and a type of silicone on top, they said. The skin is not only touch-sensitive, but also ultrathin and flexible, the researchers reported in their findings, published online March 22 in the journal Advanced Functional Materials.

In addition to helping people who wear prosthetics, the solar-powered skin could one day help robots sense touch, the researchers said. [Super-Intelligent Machines: 7 Robotic Futures]

Graphene, which makes up the third layer of the artificial skin, is a highly flexible type of the mineral graphite. The material is just a single atom thick, stronger than steel and electrically conductive. Because graphene is clear, 98 percent of sunlight that hits its surface can pass directly through it, making it an ideal material to use with solar cells, the researchers said. Dahiya and his team initially considered other energy sources for the skin, including vibration-based energy-harvesting and triboelectric processing (a fancy name for static electricity). But solar energy made the most sense, in part because it generated the most electricity, Dahiya told Live Science.

The researchers tested out the skin by putting it on a bionic hand called an i-limb, Dahiya said. Light that was shined on the skin instantaneously powered the tactile senses on it, he said.

"Human skin is an incredibly complex system capable of detecting pressure, temperature and texture through an array of neural sensors which carry signals from the skin to the brain," Dahiya said in a statement.

The new skin allowed the prosthetic hand to perform "challenging tasks, like properly gripping soft materials, which other prosthetics can struggle with," Dahiya said. In addition, the skin can detect pressures as low as 0.01 lbs. per square inch (0.11 kilopascals), he said.

The skin needs just 20 nanowatts of power per 0.1 square inches (1 square centimeter). To put that in perspective, a regular light-emitting diode (LED) light bulb takes about 5 watts to shine; 1 nanowatt is one-billionth of a watt.

After the researchers submitted their paper for publication, they figured out how to store solar energy in the skin using graphene-based devices, Dahiya said.

This technology could also help robots make safer decisions when they interact with people, he added. [9 Odd Ways Your Tech Devices May Injure You]

"A robot working on a construction line, for example, is much less likely to accidentally injure a human if it can feel that a person has unexpectedly entered their area of movement and stop [moving] before an injury can occur," Dahiya said in the statement.

The group's next goal is to develop a similar technology that can power the prosthetic hand itself, including its motors, Dahiya said.

"This could allow the creation of an entirely energy-autonomous prosthetic limb," he said.

Original article on Live Science.

A spongy new super-material could be lighter than the flimsiest plastic yet 10 times stronger than steel.

The new super-material is made up of flecks of graphene squished and fused together into a vast, cobwebby network. The fluffy structure, which looks a bit like a psychedelic sea creature, is almost completely hollow; its density is just 5 percent that of ordinary graphene, the researchers said.

What's more, though the researchers used graphene, the seemingly magical properties of the material do not totally depend on the atoms used: The secret ingredient is the way those atoms are aligned, the scientists said.

"You can replace the material itself with anything," Markus J. Buehler, a materials scientist at the Massachusetts Institute of Technology (MIT) said in a statement. "The geometry is the dominant factor. It's something that has the potential to transfer to many things."

Graphene, a material made up of flaky sheets of carbon atoms, is the strongest material on Earth — at least in 2D sheets. On paper, ultrathin sheets of graphene, which are just an atom thick, have unique electrical properties and indomitable strength. Unfortunately, these properties don't easily translate to 3D shapes that are used to build things. [7 Technologies That Transformed Warfare]

Past simulations suggested that orienting the graphene atoms a specific way could enhance strength in three dimensions. However, when researchers tried to create these materials in the lab, the results were often hundreds or thousands of times weaker than predicted, the researchers said in the statement. 

Stronger than steel

To address this challenge, the team got down to basics: analyzing the structure at the atomic level. From there, the researchers created a mathematical model that can accurately predict how to create remarkably strong super-materials. The researchers then used precise amounts of heat and pressure to produce the resulting curvy, labyrinthine structures, known as gyroids, which were first mathematically described by a NASA scientist in 1970.

"Actually making them using conventional manufacturing methods is probably impossible," Buehler said.

The material's strength comes from its enormous surface-area-to-volume ratio, the researchers reported in a study published Jan. 6 in the journal Science Advances. In nature, sea creatures like coral and diatoms also leverage a large surface-area-to-volume ratio to achieve incredible strength at tiny scales.

"Once we created these 3D structures, we wanted to see what's the limit — what's the strongest possible material we can produce," study co-author Zhao Qin, a civil and environmental engineering researcher at MIT, said in the statement.

The scientists created a series of models, built them, and then subjected them to tension and compression. The strongest material the researchers created was about as dense as the lightest plastic bag, yet stronger than steel.

One obstacle to creating these superstrong materials is the lack of industrial manufacturing capability for producing them, the researchers said. However, there are ways the material could be produced at larger scales, the scientists said

For instance, the actual particles could be used as templates that are coated with graphene through chemical vapor deposition; the underlying template could then be eaten or peeled away using chemicals or physical techniques, leaving the graphene gyroid behind, the researchers said.

In the future, massive bridges could be made of gyroid concrete, which would be ultrastrong, lightweight, and insulated against heat and cold because of all the myriad air pockets in the material, the researchers said.

Originally published on Live Science.

A tiny electronic chip just three atoms thick could yield advanced circuits that are powerful, flexible and transparent, researchers said in a new study. The scientists said the chip demonstrates a new way to mass-produce atomically thin materials and electronics.

These materials could be used to develop electronic displays on windows or windshields, along with powerful microchips in which circuitry spreads not just two-dimensionally but also rises three-dimensionally, the researchers said.

For more than 50 years, silicon has been the backbone of the electronics industry. However, as silicon transistors reach the limit of miniaturization, scientists worldwide are investigating new materials that could serve as the foundation of even tinier devices. [10 Technologies That Will Transform Your Life]

In the past decade or so, researchers discovered that atomically thin materials could serve as the basis of electronic devices. For instance, sheets of graphene — a material related to the "lead" in pencils — are each just one carbon atom thick. Graphene is an excellent conductor of electricity, making it ideal for use in wiring.

However, previous research found that graphene is not a semiconductor, whereas silicon is. This means that graphene cannot easily be used in transistors, the microscopic switches that lie at the heart of electronic circuits. A semiconductor can act either as a conductor or insulator to enable or disable the flow of electricity. Transistors are typically made of semiconductors, relying on the properties of these materials to flick on and off to symbolize bits of data as digital ones and zeroes.

Instead of graphene, therefore, some researchers are exploring molybdenite, or molybdenum disulfide (MoS2), for use in advanced electronics. Molybdenum disulfide is a semiconductor, and the new study finds that molybdenum disulfide transistors "can be switched on and off significantly better than graphene and somewhat better than silicon," said study senior author Eric Pop, an electrical engineer at Stanford University in California.

Moreover, films of molybdenum disulfide can be as thin as only three atoms, each consisting of a sheet of molybdenum atoms sandwiched between two layers of sulfur atoms. A single-molecule layer of molybdenum disulfide is only six-tenths of a nanometer thick. In contrast, the active layer of a silicon microchip is up to about 100 nanometers thick, Pop said. (A nanometer is a billionth of a meter; the average human hair is about 100,000 nanometers wide.)

These single-molecule-thin chips would be not only flexible, but also transparent. "What if your window was also a television, or you could have a heads-up display on the windshield of your car?" study lead author Kirby Smithe, an electrical engineer at Stanford University, said in a statement.

Scientists have struggled to find ways to mass produce extraordinarily thin layers of materials such as graphene and molybdenum disulfide. For example, initial experiments with graphene involved ripping layers of the material off a rock using sticky tape, a messy technique likely of no practical use in large-scale manufacturing, Pop said.

Now, Pop and his colleagues have developed a new strategy to mass produce molybdenum disulfide chips. "We finally don't have to rely on the Scotch-tape method of producing these extraordinarily thin materials," Pop told Live Science.

To create their ultrathin chip, the scientists incinerated small amounts of molybdenum and sulfur and then used the resulting vapor to form molecule-thin layers of molybdenum disulfide on a variety of surfaces, such as glass or silicon. "We went through a lot of painstaking trial and error to find the right combination of temperature and pressure to help grow these layers in a repeatable manner," Pop said.

Using this new technique, the researchers manufactured single-molecule-thick molybdenum disulfide chips measuring about 0.06 inches (1.5 millimeters) wide. These chips are each about 25 million times wider than they are thick, the researchers said.

To show how circuits might get etched onto these single-molecule-thick chips, the scientists used electron beams to carve the Stanford University logo onto the molybdenum disulfide films. The researchers also etched portraits of the two major-party candidates in the 2016 U.S. presidential election, Hillary Clinton and Donald Trump.

"Perhaps seeing portraits etched into a three-atom-thick canvas will inspire future researchers in ways we can't even imagine yet," Pop said in a statement.

The scientists will now focus on ways to make these films uniform across their entirety, and on building actual circuits from them, Pop said. "We can imagine putting molybdenum sulfide layers onto silicon layers, to build microchips vertically instead of just horizontally," Pop said. "It would be much easier to shuffle energy around such 3D architectures than conventional flat architectures."

Further studies could also explore ways to delicately remove molybdenum disulfide layers from the surfaces on which they are manufactured and transfer them onto materials such as cloth or paper. One strategy for doing this might involve a relatively well-known industrial process that would coat the single-molecule-thin film with a sticky, flexible plastic polymer and then gently peel this combination off a surface.

"This sounds a lot like using Scotch tape, but it'd involve uniform polymer films that can be peeled off with constant force in an automated and much more controlled way," Pop said.

The scientists detailed their findings online Dec. 1 in the journal 2D Materials.

Original article on Live Science.

Night-vision windshields on cars might one day be possible with advanced thermal imaging technology based on flexible, transparent, atomically thin sheets of carbon, researchers say.

Thermal imaging lets people see the invisible infrared rays that objects shed as heat. Thermal imaging devices have helped soldiers, police, firefighters and others see in the dark and in smoky conditions so they can better do their jobs.

Currently, many thermal imaging devices need cooling systems to filter out background heat in order to create useful images. However, these cooling systems complicate the design of the devices, increasing their cost and bulkiness. [Top 10 Inventions that Changed the World]

Now researchers have developed a new thermal imaging system based on sheets of graphene, which are each made of a single layer of carbon atoms arranged in a honeycomb pattern. Graphene is extraordinarily strong — about 200 times stronger than steel by weight — and highly electrically conductive.

The heart of the device is a square patch of graphene combined with microscopic silicon devices (MEMS). This square patch serves as the thermal sensor, converting thermal signals into electrical signals.

"Graphene is not only great for transistors and great for reinforcing structural materials, but it's also one of the very best materials we know for infrared detection," said study co-author Tomás Palacios, an electrical engineer at the Massachusetts Institute of Technology.

Instead of using a cooling system, the researchers isolated the thermal sensor from the rest of the device. They did this by using strips of graphene to suspend the thermal sensor in the open air, where it could detect incoming heat. These strips also convey electrical signals from the thermal sensor to the rest of the device.

The scientists found that their device could make out the heat signature of a human hand at room temperature without needing cooling fluids, known as refrigerants. The researchers suggest their findings could one day lead to flexible, transparent, low-cost thermal imaging systems.

"The advantage of significantly reducing the cost and increasing the performance of infrared imagers is that now you can start introducing these cameras in many new places," Palacios told Live Science. "For example, in the future, we can have infrared detectors integrated in every cellphone and every laptop. That means that in the future, you can control them just by waving your hand in front of them."

Although computers nowadays can use regular cameras to recognize gestures, "it takes a lot of computing power to identify where your hands are and how they're moving," Palacios said. "By using an infrared sensor, imaging of the body is simplified, since it's very easy for thermal imaging to identify the contours of the human body with respect to backgrounds, which tend to be at a lower temperature."

Thin, flexible, transparent thermal imaging systems "could also be integrated into the windshields of vehicles," Palacios said. "You would be able to view night-vision systems in real time without blocking a driver's regular view of the road."

The scientists detailed their findings online Oct. 15 in the journal Nano Letters.

Follow Live Science @livescience, Facebook & Google+. Original article on Live Science.

Origami-inspired graphene paper that can fold itself could be used to create anything from miniature robots to artificial muscles, according to a new study.

Scientists from Donghua University in China have demonstrated that gently heating a sheet of graphene paper, which is extraordinarily strong (about 200 times stronger than steel by weight), could make it fold into a device that is able to walk forward and backward. And, in a first for this kind of self-folding material, they showed it could also change directions.

The research could help scientists develop self-folding structures and devices for modern applications, including wirelessly controlled micro robots, artificial muscles and devices for tissue engineering, said Jiuke Mu, a Ph.D. student at Donghua University and one of the material’s inventors. [The 6 Strangest Robots Ever Created]

"In the near future, it even could bring changes to people's lives," Mu told Live Science, giving the example of smart clothing, "which could change its shape and style in response to body temperature, environmental changes or other gentle stimulations.”

The technology relies on specially treating sections of graphene paper so that they naturally absorb water vapor from the atmosphere, the researchers said. When the paper is heated, this water is released, causing those sections to shrink and bend. When the heating stops, this process is reversed.

Careful placement of these treated sections made it possible to create various self-folding objects, including the walking device, a self-assembling box and an artificial hand that can grasp and hold objects five times heavier than itself.

 The researchers determined the 3D shape into which the paper folds simply by altering the placement and width of the specially treated areas, with wider sections bending more than narrower ones.

The caterpillarlike walking device was created by building a rectangular sheet of graphene paper with three treated bands running across it that got progressively wider from front to back. When the sheet was lit with a near-infrared light, the bending of these sections caused the sheet to curve into an arch.

But the varying widths of these sections meant the rear of the sheet curved more than the front, so when the light was switched off and the sheet relaxed, the device stretched forwards. The response of the material was so quick that five of these steps took only 2 seconds. By heating just one side of the sheet, the researchers were also able to make the device turn, because one side would bend more than the other.

Self-folding materials have become a major topic of research in recent years, with particular focus on so-called active polymers, materials that convert other forms of energy into mechanical work. But studies to date have often relied on electrical circuitry, unusual environmental conditions or complicated combinations of materials, which tend to be fragile.

By making their devices entirely out of graphene — a one-atom-thick sheet of carbon that is both incredibly strong and very stretchy — Mu and his colleagues created a device that was still 90 percent effective, even after being folded 500 times. The material also has an energy-conversion rate of 1.8 percent, which is considerably better than the 1 percent or lower achieved by other active polymers, Mu said. [7 Cool Uses of 3D Printing in Medicine]

In addition to having the potential to inspire self-folding devices, the researchers said graphene paper could eventually be used to create artificial muscles. The stress generated by one of the paper devices was nearly two orders of magnitude higher than that of mammalian skeletal muscles, the researchers said.

"Compared with other kinds of self-folding materials, the all-graphene-based structure is simpler, its response behavior is faster and the output is more efficient," Mu said. "More importantly, its origami and walking behavior is remotely controlled."

Pure graphene can be costly and time-consuming to create, though, so the researchers used graphene oxide (GO) to create their paper. This material, Mu said, costs as little 1 Yuan (or 16 cents in U.S. dollars) per gram.

The researchers used GO nanosheets as building blocks to construct larger sheets before carrying out what's known as a reduction reaction to remove oxygen atoms from the GO. This converts the material into reduced GO (rGO), which does not have such impressive properties as pristine graphene, but still shares many of the same characteristics.

Crucially, though, the scientists treated areas of the GO paper with polydopamine (PDA) before carrying out the reduction reaction, which prevented these sections of GO from being reduced. Unlike the rest of the paper, these specially treated areas readily absorb water vapor, giving them the ability to bend.

The team's results were described in a paper published Nov. 6 in the journal Science Advances, but Mu said there is still a ways to go before any practical applications of the paper can be realized.

"We believe there is still room for improvement in the energy-conversion efficiency," he said. "Secondly, we think that as the device scales down in size, especially to nanoscale, its properties and origami performance would change significantly. Therefore we are also interested in developing a nano-size all-graphene origami device."

Follow Live Science @livescience, Facebook & Google+. Original article on Live Science.

Atom-thin layers of carbon can be turned into superconductors — extraordinary materials that conduct electricity without dissipating energy, physicists say. The findings could help lead to advanced magnetic sensors for brain scanning, the researchers added.

The form of carbon found in pencils is graphite, which is made of sheets of carbon stacked atop each other. The sheets are known as graphene, and they are made of a single layer of carbon atoms arranged in a honeycomb pattern.

Graphene is extraordinarily strong — about 200 times stronger than steel by weight. Graphene is also highly electrically conductive, and scientists worldwide are researching whether it could be used in advanced circuitry and other electronic devices. [8 Chemical Elements You've Never Heard Of]

Although graphene has many spectacular electronic properties, until now superconductivity was a notable exception. Superconductors conduct electricity with zero resistance, and so can lead to more efficient power lines. (Power companies typically lose about 7 percent of their energy to heat caused by resistance in transmission wires.)

Superconductivity was previously seen in graphite. Theoretical models suggested that graphene could also become superconducting, if adorned with additives.

Now, an international team of scientists has created the first-ever superconducting graphene by coating it with lithium atoms.

"Many groups have tried for many years to achieve superconductivity with graphene,"study principal investigator Andrea Damascelli, director of the University of British Columbia's Quantum Matter Institute in Vancouver, told Live Science. "The way you prepare the samples is key."

Scientists at the Max Planck Institute for Solid State Research in Stuttgart, Germany, created the graphene sheets. Researchers at the University of British Columbia then coated the graphene with lithium atoms.

Previous attempts to create superconducting lithium-coated graphene failed because the coating techniques introduced sources of instability, such as warmth. This instability made lithium atoms scatter around in ways that kept the graphene from superconducting.

Instead, Damascelli and his colleagues coated their graphene sheets with lithium in ultra-high-vacuum conditions at about minus 450 degrees Fahrenheit (minus 268 degrees Celsius), just about 5 degrees above absolute zero.

Superconductivity relies on electrons not repelling each other as they do in ordinary materials, but instead forming delicate pairs that can flow through superconductors effortlessly. Electrons in these pairs are held together by phonons, or vibrations of the superconductor's atoms. The lithium atoms enhanced the phonon-binding of electrons in the graphene, allowing superconductivity to occur at minus 449 degrees F (minus 267 degrees C).

The researchers do not think superconducting graphene will be used to develop more efficient power lines. Rather, Damascelli suggests it could be used in extraordinarily sensitive magnetic sensors known as SQUIDs, or superconducting quantum interference devices, which can scan brain activity with exquisite detail.

"It could lead to a 100-fold increase in the sensitivities we currently have," Damascelli said. "That's where superconductivity could really have a huge impact."

The researchers hope to better understand the nature of graphene's superconductivity, which could help them find ways to make it superconduct at warmer temperatures, Damascelli said.

The scientists detailed their findings online Sept. 7 in the journal Proceedings of the National Academy of Sciences.

Follow Live Science @livescience, Facebook & Google+. Original article on Live Science.

Graphene, a form of carbon famous for being stronger than steel and more conductive than copper, can add another wonder to the list: making light.

Researchers have developed a light-emitting graphene transistor that works in the same way as the filament in a light bulb.

"We've created what is essentially the world's thinnest light bulb," study co-author James Hone, a mechanical engineer at Columbia University in New York, said in a statement.

Scientists have long wanted to create a teensy "light bulb" to place on a chip, enabling what is called photonic circuits, which run on light rather than electric current. The problem has been one of size and temperature — incandescent filaments must get extremely hot before they can produce visible light. This new graphene device, however, is so efficient and tiny, the resulting technology could offer new ways to make displays or study high-temperature phenomena at small scales, the researchers said. [8 Chemical Elements You've Never Heard Of]

Making light

When electric current is passed through an incandescent light bulb's filament — usually made of tungsten — the filament heats up and glows. Electrons moving through the material knock against electrons in the filament's atoms, giving them energy. Those electrons return to their former energy levels and emit photons (light) in the process. Crank up the current and voltage enough and the filament in the light bulb hits temperatures of about 5,400 degrees Fahrenheit (3,000 degrees Celsius) for an incandescent. This is one reason light bulbs either have no air in them or are filled with an inert gas like argon: At those temperatures tungsten would react with the oxygen in air and simply burn.

In the new study, the scientists used strips of graphene a few microns across and from 6.5 to 14 microns in length, each spanning a trench of silicon like a bridge. (A micron is one-millionth of a meter, where a hair is about 90 microns thick.) An electrode was attached to the ends of each graphene strip. Just like tungsten, run a current through graphene and the material will light up. But there is an added twist, as graphene conducts heat less efficiently as temperature increases, which means the heat stays in a spot in the center, rather than being relatively evenly distributed as in a tungsten filament. 

Myung-Ho Bae, one of the study's authors, told Live Science trapping the heat in one region makes the lighting more efficient. "The temperature of hot electrons at the center of the graphene is about 3,000 K [4,940 F], while the graphene lattice temperature is still about 2,000 K [3,140 F]," he said. "It results in a hotspot at the center and the light emission region is focused at the center of the graphene, which also makes for better efficiency." It's also the reason the electrodes at either end of the graphene don't melt.

As for why this is the first time light has been made from graphene, study co-leader Yun Daniel Park, a professor of physics at Seoul National University, noted that graphene is usually embedded in or in contact with a substrate.

"Physically suspending graphene essentially eliminates pathways in which heat can escape," Park said. "If the graphene is on a substrate, much of the heat will be dissipated to the substrate. Before us, other groups had only reported inefficient radiation emission in the infrared from graphene."

The light emitted from the graphene also reflected off the silicon that each piece was suspended in front of. The reflected light interferes with the emitted light, producing a pattern of emission with peaks at different wavelengths. That opened up another possibility: tuning the light by varying the distance to the silicon.

The principle of the graphene is simple, Park said, but it took a long time to discover.

"It took us nearly five years to figure out the exact mechanism but everything (all the physics) fit. And, the project has turned out to be some kind of a Columbus' Egg," he said, referring to a legend in which Christopher Columbus challenged a group of men to make an egg stand on its end; they all failed and Columbus solved the problem by just cracking the shell at one end so that it had a flat bottom.

The research is detailed in today's (June 15) issue of Nature Nantechnology.

Follow us @livescience, Facebook & Google+. Original article on Live Science.

Updated at 12:31 p.m. ET.

Graphene is often touted as a miracle material— it easily conducts electricity and it's hundreds of times stronger than steel. But now tests of real-world samples of graphene show that while the carbon material is possibly the strongest material produced today, it's also as brittle as ordinary ceramic.

Result? It can crack.

A team of scientists from Rice University and the Georgia Institute of Technology tested small pieces of "bilayer" graphene, two single-atom-thick sheets of pure carbon resting one atop the other,by making tiny cracks in them with focused beams of ions. They then pulled the graphene, to see how fast the cracks expanded until the material broke. [8 Chemical Elements You've Never Heard Of]

"It's very sensitive to [the] presence of [a] crack. In steel if you have a crack, there, it's not so dangerous. Steel has a huge resistance to crack extension. Graphene is more like window glass," said Ting Zhu, an associate professor of mechanical engineering at Georgia Tech and one of the authors of the study.

The measure of a material's resistance to cracks, called fracture toughness, is not just the tensile strength — how likely it is to break when tugged on. It also measures how much punishment a given substance can take before cracking when being twisted. Metals, for instance, are ductile; it takes a lot of twisting and bending to break a spoon. A piece of glass resists twisting and doesn't stretch, but it breaks quickly if any twisting or pulling force is applied past a certain threshold, and even a tiny crack will make it shatter.

Zhu, working with Jun Lou at Rice, found that graphene with cracks is 10 times more prone to breakage than steel, and closer in fracture toughness to aluminum oxide or silicon carbide-based ceramics.

The relatively low fracture toughness means that it takes only a small crack in a piece of graphene to weaken it. And such small cracks are a natural consequence of making graphene.

Graphene is made in several ways, among them chemical vapor deposition, in which carbon vapor is allowed to cool and settle on a surface, and exfoliation, in which graphite (from which graphene is derived) is put into a solvent. The sheets of graphene can be large in the former case, but they aren't perfect. The resulting lattice of carbon atoms that makes up the graphene has small defects — an atom missing or misaligned here and there. The defects won't make much difference when using graphene as a conductor or semiconductor, but for mechanical applications, such as making flexible displays or boosting structural strength of other materials, the imperfections start to matter.

Perfect graphene can take about 100 Gigapascals (14 million pounds per square inch) of force before it breaks. But the imperfect graphene the researchers made can withstand only a tiny fraction of that, about 4 Megapascals (580 pounds per square inch).

The experiments aren't just important for the study of graphene. Other materials that can take on a two-dimensional structure might behave in a similar way, and as such the new research, detailed today (April 29) in the journal Nature Communications, might offer important insights.

"This kind of modeling could be applied to study many other 2D materials, such as molybdenum disfulfide or boron nitride," Zhu said.

Editor's Note: This article was updated to correct the last quote, which had aluminum sulfide instead of molybdenum disfulfide.

Follow us @livescience, Facebook& Google+. Original article on Live Science.

Graphene, single-atom-thick sheets of pure carbon, is lighter than steel but many times stronger, with better electrical conductivity than copper. It's even transparent. One day graphene could support flexible electronics, solid lubricants and even a space elevator.

But before that happens the stuff must be mass-produced, and a team led by Jonathan Coleman, a professor of chemical physics at Ireland's Trinity College in Dublin, thinks they've found a way to do it. They put graphite (from which graphene is derived) into a solution and stirred it with rotors moving at thousands of revolutions per minute — which worked even with an ordinary blender. Their work is detailed in the April 20 issue of the journal Nature Materials.

Making lots of graphene isn't easy. There are a number of methods, such as chemical vapor deposition, which involves turning carbon into a vapor that collects on a surface, heating silicon carbide (SiC) to leave the pure carbon — graphene — behind, or simply tearing off sheets of single carbon atoms from blocks of graphite. The latter method is called the "Scotch Tape" method, because initially tape was stuck to a graphite block and the graphite was just peeled off. [8 Chemical Elements You've Never Heard Of]

Current methods, though, are expensive and difficult to carry out on an industrial scale. On top of that, to get the wonder-material properties, graphene has to be of high quality — the carbon atoms that form the sheets have to be in near-perfect hexagonal patterns.

Making graphene

Coleman said his team started from methods involving bombarding graphene in liquid form with high-frequency sound. They wanted to make the material without the ultrasound, simplify the process and cut energy costs. When they tried stirring the liquid, they produced high-quality flakes of graphene.

"Under the electron microscope it looks just like a diagram in a textbook," Coleman said.

The stirring works in two ways. First, the liquid is spinning around and it's not moving at the same speed throughout. So the grains of graphite get hit with more force on one side than the other, a phenomenon called shear. Carbon atoms in graphite are arranged in hexagonal patterns like chicken wire, piled on top of each other in layers. The bonds between the layers are weaker than the bonds within them, so when the buffeting in the water breaks up the grains, they tend to break into flat sheets — graphene.

Ordinarily the sheets of graphene would stick back together in clumps. But that's where the solvent comes in. One of the solvents they used was N-methyl-2-pyrrolidone, common to the petrochemical industry. As the sheets of graphene separate the solvent sticks to the carbon atoms. That keeps the single sheets of graphene separate, with the result being a liquid solution full of micrometer-size flakes of pure, high-quality graphene.

What's next for kitchen-made graphene

Though the sheets are tiny, this process can make lots of them. And unlike other processes for making graphene, if some of the carbon doesn't make the perfect sheets that's OK, because the non-graphene carbon can be filtered out and put through the process again.

Besides chemical solvents the process also works with surfactants in water. The team even tested a kitchen blender using ordinary dishwashing liquid.

The researchers made up to 21 grams (about seven-tenths of an ounce) of graphene using 300 liters (80 gallons) of water and surfactant. That may not sound like much, but it's enough to cover about 290 square feet. Coleman said he and his team are working with a British company, Thomas Swan, exploring how to commercialize this production method. 

Other research teams are looking at other methods. A start-up in Philadelphia, Pa., Graphene Frontiers, got a $744,600 grant from the National Science Foundation to explore chemical vapor deposition, what it calls a "roll-to-roll" process.

And there are still challenges to making the equipment used in Coleman's study: A small rotor in a blender or laboratory table is not moving as fast as a large one in an industrial vat. But the fact that even a blender works bodes well for future manufacturing — it means the equipment should be relatively simple. Coleman noted there was some surprise that a blender could generate enough energy.

Follow us @livescience, Facebook & Google+. Original article on Live Science.

This article was originally published at The Conversation. The publication contributed the article to LiveScience's Expert Voices: Op-Ed & Insights.

The proposal of an ultra-thin condom made from graphene and latex brings design of the contraceptive into the 21st century. We have yet to see a prototype, but the developers at the University of Manchester said the thinnest and strongest condom ever made would enhance sensation during sex, which they hope will encourage more condom use.

Graphene is a form of carbon that has been touted a “miracle material”, can be one-atom thick the strongest ever measured and a replacement for silicone. James Hone, an engineering professor from Columbia University, said it was so strong that “it would take an elephant, balanced on a pencil, to break through a sheet of graphene the thickness of Saran Wrap [cling film]”.

The plan at Manchester is to combine graphene with latex, currently the main material used in making condoms, to make their own. But will enhancing sensation really make people use condoms more?

Finding the right fit

Despite condoms being one of the best ways to prevent pregnancy and sexually transmitted infections (STIs) such as chlamydia and HIV, they’re still unpopular for a variety of reasons.

There has been a lot of research carried out into understanding how often condoms are being used, what problems are associated with using them and people’s attitudes towards them. An array of social and psychological factors influence how much we use condoms, such as loss of pleasure, the smell (commonly from latex) and arguments that they cause some men to lose their erection.

People tend to weigh up the perceived pros and cons of condoms and safer sex. There is a spectrum of condom use from people not using them at all, to using them inconsistently or attempting to use them and failing. And a growing body of research is telling us more about the errors and problems people have when using condoms – including fit, breakages and spillages.

Cops and rubbers

There have been many attempts to promote condom use across the globe. In Thailand for example, attempts were made throughout the 1980s to increase condom use to lower the country’s high birth rates and as part of an HIV prevention programme in the 1990s. The government worked with brothel owners to enforce condom use, there was a mass media campaign and police officers distributed condoms through something called the “cops and rubbers” initiative.

Thailand’s ‘Mr Condom’ at TEDx

Despite some success, problems remain with condom use still low in rural areas especially. This points to a lack of awareness and availability of condoms as a reason for low usage. But even in the West where condoms are widely available and sexual education programmes raise awareness, high rates of STIs persist. So is it really always about a lack of availability?

Condoms for the unclean?

A review of 268 qualitative studies in The Lancet found seven key themes reported by young people about unsafe sex, including that they were stigmatising or indicated a lack of trust. Another was in the perception of potential sexual partners as “clean” or “unclean” – so if a partner was deemed the former it was OK not to use a condom. Other social expectations, such as the fear of appearing “easy” or not also came into play.

Given social reasons influence sexual behaviour, new technology such as the graphene condom (and another idea exploring “shape memory”) won’t necessarily improve attitudes toward using condoms. It’s clear there’s still some way to go here.

But emphasising pleasure could be a new narrative that encourages some to weigh up the pros and cons a bit differently. For the most part, attempts to encourage young people to use condoms employ scare tactics that emphasise the consequences of not using them. But some of our research has found that young men actually reject these fear narratives and want a different tone in health communications. So a condom that emphasises “enhanced pleasure” could be effective for these groups. We are also looking into the attitudes of older adults towards condom use, as they remain sexually active.

The social and cultural forces at play that influence how young people act in the bedroom means merely providing information and condoms isn’t enough to bring about changes in sexual behaviour. While scientific advances in sexual health such as graphene condoms could be very important, getting people to wear them in the first place requires a deeper understanding of the social and cultural forces at work.

Karen Lorimer receives grant funding from the Chief Scientist Office, Scottish Government.

Jen MacDonald is funded by a Glasgow Caledonian University PhD stipend.

This article was originally published at The Conversation. Read the original article. The views expressed are those of the author and do not necessarily reflect the views of the publisher. This version of the article was originally published on LiveScience.

No flash? No problem. A new imaging sensor could soon make it possible for photographers to take clear, sharp photos, even in dim lighting.

Created by a team of researchers at Nanyang Technological University (NTU) in Singapore, the new sensor is highly sensitive to both visible and infrared light, which means it could be used in everything from the family Nikon to surveillance and satellite cameras. 

The sensor, which is 1,000 times more sensitive to light than the imaging sensors of most of today's cameras, gets this high photoresponse from its innovative structure.

It's made of graphene, a super strong carbon compound with a honeycomb structure that is as flexible as rubber, more conductive than silicon and which resists heat better than a diamond.

Graphene, which is a one atom-thick layer of the mineral graphite, has already earned a reputation as the building material of the future. Andre Geim and Konstantin Novoselov took home the Nobel Prize in physics in 2010 for their work with the compound.

The inventor of the new sensor, Wang Qijie, an assistant professor at NTU's School of Electrical and Electronic Engineering, said this is the first time that a broad-spectrum, high photosensitive sensor has been made using pure graphene.

"We have shown that it is now possible to create cheap, sensitive and flexile sensors from graphene alone," said Wang. "We expect our innovation will have great impact not only on the consumer imaging industry, but also in satellite imaging and communication industries, as well as the mid-infrared applications."

Wang said the key to his new sensor is the use of "light-trapping" nanostructures that use graphene as a base. The nanostructures hold onto light-generated electron particles for much longer than conventional sensors.

This results in a stronger than usual electric signal, which can be processed into an image, like a photograph captured by a digital camera.

Most of today's camera sensors use a complementary metal-oxide semiconductor as a base. But Wang said that his graphene base is far more effective, producing clearer, sharper photos.

And, according to Wang, he even took current manufacturing practices into account when designing this new sensor. In principle, the camera industry will be able to keep using the same process to make its sensors, but simply switch out the base materials for graphene.

If the industry chooses to adopt his design, Wang said it could lead to cheaper, lighter cameras with longer battery lives for all.

Email asklizzyp@gmail.com or follow her @techEpalermo. Follow us @TechNewsDaily, on Facebook or on Google+.

This Behind the Scenes article was provided to LiveScience in partnership with the National Science Foundation.

We seldom think about it, but electromagnetic waves are an integral part of our everyday life. On any given day, we employ cell phones, TVs, radios and microwave ovens to manipulate, generate and detect electromagnetic waves for the purpose of transmitting information or energy. Even our own bodies interact with these waves, when our eyes detect and process visible light.

Although all electromagnetic waves travel at the speed of light, or approximately 186,282 miles per second, the length and frequency of the wave determines its ultimate use. The longest waves, also known as radio waves, can travel far distances making them perfect for transmitting data to televisions, radios and cell phones. The next region of the spectrum is microwaves. These smaller waves carry information to satellites and weather radars, as well as impart energy via microwave ovens. The remaining electromagnetic spectrum consists of terahertz, infrared, visible and ultraviolet radiation as well as x-rays and gamma rays. As with radio and microwaves, these regions are continuously explored and researched for new device applications.

Until recently, the THz frequency range — located between the far infrared and the high frequency microwave bands — was one of the least exploited regions of the electromagnetic spectrum. With the ability to carry more information than its neighboring radio and microwave frequencies, THz waves have shown great potential for applications in healthcare screening, chemical sensing, object detection and high-speed wireless communications. However, most THz sources and devices used today are bulky and expensive, which limits their application and availability. The development of cheap, compact and efficient THz materials and devices would expand if not catalyze research on this region of the spectrum. The recent development of a new naturally-occurring and artificially-engineered material is closing this so-called "THz gap."

A research group led by Huili (Grace) Xing at the University of Notre Dame, with support from the National Science Foundation, has been actively developing graphene-based devices capable of efficiently manipulating THz waves. Graphene, an atom-thick sheet of bonded carbon atoms, can modulate or vary the properties of THz waves — making it an ideal choice for THz-based devices and systems. "Graphene is a miracle material for THz applications," says Xing. "This is owing to its two-dimensional nature, which leads to extraordinary electrical and optical properties, and ease of fabrication, which leads to unprecedented degrees of freedom in terms of device and system design."

Xing, her colleagues and students at the University of Notre Dame aim to develop cheap, compact and high-performance graphene-based THz systems such as cameras and high speed communication chips. "Understanding the interaction of graphene with THz waves is the key for developing these THz devices," Xing says. Her group relies on numerical simulations and theoretical calculations to engineer their devices before fabricating them in the laboratory.

The graphene-based THz devices proposed and developed by the group so far consist of a layer of graphene and another two-dimensional layer of electrons separated by a thin insulator. The graphene layer affects the properties of the waves passing through the material, while the insulating layer serves to create a nonconductive space between the graphene and second electron layer. By applying a voltage between these layers, the absorption of THz waves can be tuned from close to zero to almost 100 percent. "It is amazing that we can observe such a strong THz response, considering that graphene is an atom-thick material," says Berardi Sensale-Rodriguez, a graduate student in Xing's group. "This is a result of the high electrical conductivity achievable in graphene, together with the possibility of constructing device structures where the electric field is enhanced in the graphene layers," explains Xing.

In a recent article published about their work ("Broadband graphene terahertz modulators enabled by intraband transitions", Nature Communications, 2012), the group reported their development of an intrinsically broadband THz modulator based on graphene sheets. In other words, a device capable of modulating THz waves in a wide range of frequencies. This modulator revealed more than double the THz manipulation of prior broadband intensity modulators. It is also the first demonstration of a graphene-based device enabled solely by intraband transitions. By adjusting the layers or transitions within the graphene material, THz waves can be tuned and manipulated. Such efficient THz modulation can result in unprecedented performance when applied to devices.

This novel application of graphene paves the way for the development of compact, cost-effective and highly efficient THz devices based on graphene and related materials. In the near future, these materials and devices may provide our everyday lives with such advances as improved communication systems and safer, more highly defined medical imaging.

Editor's Note: The researchers depicted in Behind the Scenes articles have been supported by the National Science Foundation, the federal agency charged with funding basic research and education across all fields of science and engineering. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author and do not necessarily reflect the views of the National Science Foundation. See the Behind the Scenes Archive.

The high-tech devices of Silicon Valley depend on tiny, hard silicon chips. Yet in an imagined future in which walls, windows and clothes act as computing devices, the hardware components would have to be soft and flexible. One research group has taken a first step toward that flexible future, combining a conductor and an insulator in the thinnest sheet possible ? just one atom thick.

"This work shows that it is possible to bring together these two materials. What we believe that opens the doors to is the ability to create these atomically thin electronics, or more-complicated stacked electronics," said Mark Levendorf, a graduate student who worked on the new material. Levendorf studies nanotech chemistry at Cornell University. 

"It's in the early phases," he added. "It's a step in the right direction toward miniaturizing things." 

Transistors — the building blocks of all modern digital computers — require a conductor, an insulator and a semiconductor. Getting two of the three into the universe's thinnest sheet is a significant feat, said Chagaan Baatar, manager of the nanoscale electronics program at the Office of Naval Research, in Arlington, Va. [Ten Computers That Changed the World]

"This is the first time researchers have succeeded in patching together two different materials with vastly different electronic properties in the same two-dimensional (2D) sheet," he said in an email to InnovationNewsDaily. 

For its conductor, the new material uses graphene, a one-atom-thick sheet of carbon that carries electrons faster than any other chemical at room temperature. Because graphene is flexible and works much faster than silicon, many researchers think it will be a key supplement to silicon in the future. Because it's transparent, it also may go into touch screens. Labs around the world are studying how to put graphene into electronic devices. 

Levendorf and his colleagues developed a technique to control exactly where they lay down the graphene and their insulator, boron nitride. With their specially patterned graphene and boron nitride, they created 1-centimeter- to 1-inch-long pieces of material through which they were able to run currents. Their tight control of where they arranged the graphene and the boron nitride meant they could direct currents in any way they wanted, which is important for building circuits, Levendorf said.

They built up their sheet through a technique that's used in industry now, so it should be easy to create larger pieces of the graphene-boron nitride material, Levendorf said.

"That's another thing we're pretty excited about," he told InnovationNewsDaily. The Cornell lab was limited to 1-inch pieces because of its equipment, but other labs have the equipment to make larger pieces, he said. 

Nevertheless, it may be a decade or longer before graphene transistors show up in people's laptops, Baatar said. The major hurdle to creating graphene-based computers is that it's impossible to stop the flow of current through graphene. That means researchers can't create transistors that turn on and off, which would be necessary to set up the logic questions that silicon digital devices use to operate.  

"The challenge is formidable," Baatar said. But not impossible: "Unless you are violating some fundamental laws of nature, I would say nothing is impossible in science," he said, "particularly when it comes to a material as unique as graphene."

Adding a semiconductor to graphene would help. Levendorf and his colleagues are working on adding molybdenum disulfide to their material. 

They published their work on their graphene-boron nitride sheet today (Aug. 29) in the journal Nature. 

This story was provided by InnovationNewsDaily, a sister site to LiveScience. You can follow InnovationNewsDaily staff writer Francie Diep on Twitter @franciediep. Follow InnovationNewsDaily on Twitter @News_Innovation, or on Facebook.

This ScienceLives article was provided to LiveScience in partnership with the National Science Foundation.

Yogesh Joglekar, assistant professor of physics at Indiana University-Purdue University Indianapolis, works on graphene and optical waveguides with balanced loss and gain, two of the hottest fields in theoretical physics. In addition, he mentors a growing number of high school and undergraduate students who are carrying out original research that is published in top-tier physics journals. A National Science Foundation CAREER grant supports his graphene research and mentoring.

Name: Yogesh Joglekar Age: 38 Institution: Indiana University-Purdue University Indianapolis (IUPUI) Field of Study: Graphene, PT-symmetric lattice systems

What inspired you to choose this field of study?

When I joined the physics department in the School of Science at IUPUI in 2005, graphene had just been discovered, and I couldn’t wait to start theoretical research on it. It is fascinating that such a day-to-day material — pencil lead — serves as a prototype for testing exotic quantum field theory predictions and will also lead to new device applications within the next decade.  It’s very exciting to be working in a field that has recently been recognized with a Nobel Prize.

My second research area is open systems with sources and sinks, such as light traveling in a medium with loss and gain. These systems are called ‘PT-symmetric lattice models’. A high-school student working with me in this field obtained some very intriguing predictions. As we tried to understand them, I realized that this is an ideal area to involve young students in high-level, original research.

What is the best piece of advice you ever received?

The inventor Thomas Edison said, "Success is 10 percent inspiration and 90 percent perspiration.” The best career advice I received was from my graduate advisor Allan MacDonald who paraphrased Edison a bit, and told me that “Success in research is ninety percent perseverance, five to seven percent inspiration, and the rest is luck.”

What was your first scientific experiment as a child?

The first ‘cool experiment’ I did as a child was a science project where my friends and I filled glass-beakers with different liquids to create lenses with different magnifying powers. We were all about 14 years old and couldn’t believe we could make magnifiers out of things like water and oil and use them to focus sunlight and start a fire.

What is your favorite thing about being a researcher?

Being a researcher at IUPUI allows me to explore questions that I find interesting and to discuss the questions and their possible answers with novices — high school, undergraduate and graduate students — and experts alike. The thrill of that (occasional) insight and of understanding something deeply and perhaps differently is my favorite part of the job.

What is the most important characteristic a researcher must demonstrate in order to be an effective researcher?

An effective researcher usually needs to have a combination of curiosity, the desire and ability to follow through, and a certain level of objectivity that is necessary to evaluate your results.  Enthusiasm, a sense of humor, and good communication skills are also important!

What are the societal benefits of your research?

The graphene research explores the possibilities of electric current flow without resistance and the production of a laser-like light via excitonic condensation. My research on PT-symmetric lattices explores the control and manipulation of the motion of light. Both of these studies lead to a deeper understanding of the flow of electric charges and electromagnetic waves, which is necessary — but not sufficient — for designing new electronic and optical materials.

An equally important benefit of theoretical physics research, particularly for young students, is that it teaches them critical thinking, model building and carrying out reality checks on their results. These skills are applicable to and required in any STEM discipline and beyond. Many young students remain interested or become interested in pursuing science careers as a result of hands-on research. So an important societal benefit of our research is that it is putting some bright students on paths to careers in science and encouraging others to be science literate in whatever fields they pursue.

Who has had the most influence on your thinking as a researcher?

Richard Feynman, one of the greatest teachers and a physics Nobel winner, has influenced me greatly over the past two decades. When I was in high school, I read ‘Surely You’re Joking, Mr. Feynman!’ and it solidified my decision to pursue physics. His intellectual abilities were exceptional. His curiosity and the drive to understand the world around him were superlative and so was his desire to convey the understanding of physics to the public at large. He was equally passionate about explaining subtle quantum physics and the effect of cold on O-rings, like those that doomed the Challenger space shuttle. He heavily influences my research, particularly when working with young students, and my teaching. 

What about your field or being a researcher do you think would surprise people the most?

People usually think that research in theoretical physics requires graduate level training. They are surprised to learn that, given the right problems, even high school students can produce original work. The youngest student co-author in my group is a 13-year-old; we have had four other high school student co-authors on two different papers. This involvement of young students in high-level research is a surprise to most people. When people hear the term “theoretical physics” they more often think of scientific genius rather than a high school or undergraduate student.

If you could only rescue one thing from your burning office or lab, what would it be?

Being a theorist, most of the important stuff is in my head. So I would just go back for thank-you gifts from my students including an XKCD web comic poster!

What music do you play most often in your lab or car?

I grew up in Mumbai (Bombay) with Marathi as my native language; I went to IIT Kanpur where Hindi was the primary language, and then came to the US where English is the main language. So my music is an eclectic collection across these three languages. I am especially partial to classical (both Indian and Western) and classic rock.

Editor's Note: The researchers depicted in ScienceLives articles have been supported by the National Science Foundation, the federal agency charged with funding basic research and education across all fields of science and engineering. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author and do not necessarily reflect the views of the National Science Foundation. See the ScienceLives archive.

This Behind the Scenes article was provided to LiveScience in partnership with the National Science Foundation.

Silicon has long been the workhorse of our digital world, but as silicon transistors shrink to the nanoscale, such factors as excessive power consumption in these devices could degrade performance.   

"The scaling of silicon transistors has driven the economy around the world for the past half century," says Jeff Welser, director of the Nanoelectronics Research Initiative at the Semiconductor Research Corporation (SRC), a consortium made up of the world's largest semiconductor manufacturers.  "The United States is the leader in microelectronics, and to maintain that leadership and to continue to drive the economy, we need to find a way to keep the device scaling going."

Many of the solutions being pursued around the world involve the adoption of new device architectures or new materials.  Bhagawan Sahu, a research physicist at the Southwest Academy of Nanotechnology (SWAN), located at the University of Texas at Austin, is part of a nationwide search to find nanoscale materials and processes that can replace silicon transistors by the year 2020.

Sahu and his colleagues at SWAN aim to make transistors that are less than 10 nanometers long and less than one nanometer thick.  To do so, they are exploring graphene, a single layer of graphite that is one of the thinnest materials in the world and possesses electron mobility (a measure of how fast electrons can move in response to external voltages) higher than silicon.  Those characteristics are attractive features and have generated tremendous interest from the semiconductor industry.

After five years of dedicated study, the group’s novel, graphene-based design was selected by the SRC as one of only a handful of device ideas to be further studied.

"Understanding the device components [at the scale of atoms] through simulations has become [critical] for these nanoscale devices," Sahu says.  "Our efforts at SWAN provide the community with the simulation results, which are obtained by virtual experiments before any real experiments are performed."

The graphene-based system that the researchers created—which they call the bilayer pseudospintronic field-effect transistor (or BiSFET)—is based on two layers of graphene separated by a super-thin insulator of air or a vacuum.  The physics of the device is based on “collective charge motion”, where a superfluid state forms at room temperature under certain conditions.

"In this structure, all of the electrons want to be in one layer or the other," Welser explains.  "By applying a very small voltage—on the order of 25 millivolts—you can get all of the charge to jump from one side to the other.  It acts like a switch, which is exactly how we want our transistors to act."

To explore this phenomenon, Sahu and his team used the NSF-supported Ranger and Lonestar 4 supercomputers at the Texas Advanced Computing Center (TACC).  The computers, by virtue of their size and power, enabled the scientists to model new material systems that cannot be easily fabricated. 

Moreover, the ability to simulate designs quickly and repeatedly allowed the researchers to experiment—virtually, with different widths, lengths, layer orientations, how layers are stacked and external voltages for graphene ribbons and flakes—to see how the variables influence the electronic properties, including the electron band gap, magnetism and other related factors.  The simulations have been critical to understanding the internal and external variables that can affect device performance.

If the SWAN researchers can overcome the challenges involved in fabricating and demonstrating the BisFET devices, the nanotransistor may be the game changer that the semiconductor industry is betting on.

"The simulations are playing a major role in elucidating the interplay of the structure and the electronic properties of graphene," Sahu says. "We're building component by component, so we have an integrated view of what each part does and how it affects the whole device."

Editor's Note:The researchers depicted in Behind the Scenes articles have been supported by the National Science Foundation (NSF), the federal agency charged with funding basic research and education across all fields of science and engineering. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author and do not necessarily reflect the views of the National Science Foundation. See the Behind the Scenes Archive.

Scientists have created the world's thinnest balloon, made of a single layer of carbon just one atom thick.

The fabric that the balloon is made of is leakproof to even the tiniest airborne molecules. It could find use in "aquariums" smaller than a red blood cell, through which scientists could peer at molecules, researchers suggested.

The balloon is made of graphite, as found in pencils, which is made of atom-thin sheets of carbon stacked on top of each other known. The sheets are known as graphene.

Graphene is highly electrically conductive, and scientists are feverishly researching whether it could find use in advanced circuitry and other devices.

"We were studying little graphene trampolines, and by complete accident, we made a graphene sheet over a hole. Then we started studying it, and saw that it was trapping gas inside," said researcher Paul McEuen, a physicist at Cornell University in Ithaca, N.Y.

By experimenting further with bubbles made of graphene, McEuen and his colleagues found the membranes were impermeable to even the smallest gas molecules, including helium.

"It's amazing that something only an atom thick can be an impenetrable barrier. You can have gas on one side and vacuum or liquid on the other, and with a wall only one atom thick, nothing would go through it," McEuen told LiveScience.

In terms of applications, McEuen suggested one possibility which he called miniature aquariums for molecules. "You could have instruments on one side of the membrane, in vacuum or air, and on the other side you would have DNA or proteins suspended in liquid," he explained. "And then you could get right up close to image the molecules, within a few angstroms," or widths of an atom.

Other potential applications include hyper-fine sensors and ultra-pure filters.

"Once you have a membrane that won't let anything past, the most interesting thing is to then poke a hole in it. Then you can detect what leaks through that hole with high sensitivity, or make sure only what you want leaks through that hole," McEuen said.

The only way gas leaked out from inside the balloons was through the glass that the bubbles were anchored on, McEuen explained.

"We need to build a better base that's more impenetrable, such as single crystal silicon. I'm confident we can make a leakproof version," McEuen said.

The scientists will detail their findings in the Aug. 13 issue of the journal Nano Letters.

• TechShop: Where Inventors' Dreams Are Made
• Forget Crystal Balls: Let the Power of Math Inform Your Future
• Innovations: Ideas and Technologies of the Future