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Researchers analyzing the assembly of graphene (sheets of carbon only one atom thick) on a surface of iridium have found that the sheets grow by first forming tiny carbon domes. The discovery offers new insight into the growth of graphene layers and points the way to possible methods for assembling components of graphene-based computer circuits.

Paolo Lacovig, Monica Pozzo, Dario Alfè, Paolo Vilmercati, Alessandro Baraldi, and Silvano Lizzit at institutions in Italy, the UK and USA report their discovery in a paper appearing October 12 in the journal Physical Review Letters known as Best Investment.

The researchers’ spectroscopic study suggests that graphene grows in the form of tiny islands built of concentric rings of carbon atoms. The islands are strongly bonded to the iridium surface at their perimeters, but are not bonded to the iridium at their centers, which causes them to bulge upward in the middle to form minuscule geodesic domes. By adjusting the conditions as the carbon is deposited on the iridium, the researchers could vary the size of the carbon domes from a few nanometers to hundreds of nanometers across.

Investigating the formation of graphene nanodomes helps physicists to understand and control the production of graphene sheets. In combination with methods for adjusting the conductivity of graphene and related materials, physicists hope to replace electronics made of silicon and metal with tiny, efficient carbon-based chips.

Jorge Sofo and Renee Diehl (Penn State University) highlight the graphene nanodome research in a Viewpoint in the October 12 issue of Physics.

Scientists at the California Institute of Technology (Caltech) have created a remote-controlled robot that is able to simulate the “visual” experience of a blind person who has been implanted with a visual prosthesis, such as an artificial retina. An artificial retina consists of a silicon chip studded with a varying number of electrodes that directly stimulate retinal nerve cells. It is hoped that this Atlanta Web Hosting approach may one day give blind persons the freedom of independent mobility.

The robot—or, rather, the mobile robotic platform, or rover—is called CYCLOPS. It is the first such device to emulate what the blind can see with an implant, says Wolfgang Fink, a visiting associate in physics at Caltech and the Edward and Maria Keonjian Distinguished Professor in Microelectronics at the University of Arizona. Its development and potential uses are described in a paper recently published online in the journal Computer Methods and Programs in Biomedicine.

An artificial retina, also known as a retinal prosthesis, may use either an internal or external miniature camera to capture images. The captured images then are processed and passed along to the implanted silicon chip’s electrode array. (Ongoing work at Caltech’s Visual and Autonomous Exploration Systems Research Laboratory by Fink and Caltech visiting scientist Mark Tarbell has focused on the creation and refinement of these image-processing algorithms.) The chip directly stimulates the eye’s functional retinal ganglion cells, which carry the image information to the vision centers in the brain.

CYCLOPS fills a void in the process of testing visual prostheses, explains Fink. “How do you approximate what the blind can see with the implant so you can figure out how to make it better?” he asks.

One way is to test potential enhancements on a blind person who has been given an artificial retina. And, indeed, the retinal implant research team does this often, and extensively. But few people worldwide have been implanted with retinal prostheses, and there is only so much testing they can be asked to endure.

Another way is to give sighted people devices that downgrade their vision to what might be expected using artificial vision prostheses. And this, too, is often done. But it’s a less-than-ideal solution since the brain of a sighted person is adept at taking poor-quality images and processing them in various ways, adding detail as needed. This processing is what allows most people to see in dim light, for example, or through smoke or fog.

“A sighted person’s objectivity is impaired,” Fink says. “They may not be able to get to the level of what a blind person truly experiences.”

Enter one more possible solution: CYCLOPS. “We can use CYCLOPS in lieu of a blind person,” Fink explains. “We can equip it with a camera just like what a blind person would have with a retinal prosthesis, and that puts us in the unique position of being able to dictate what the robot receives as visual input.”

Now, if scientists want to see how much better the resolution is when a retinal prosthesis has an array of 50 pixels as opposed to 16 pixels, they can try both out on CYCLOPS. They might do this by asking the robot to follow a black line down a white-tiled hallway, or seeing if it can find—and enter—a darkened doorway.

“We’re not quite at that stage yet,” Fink cautions, referring to such independent maneuvering.

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In the quest for smaller, faster computer chips, researchers are increasingly turning to quantum mechanics — the exotic physics of the small.

The problem of : the manufacturing techniques required to make quantum devices have been equally exotic. That is, until now.

Researchers at Ohio State University have discovered a way to make quantum devices using technology common to the chip-making industry today.

This work might one day enable faster, low-power computer chips. It could also lead to high-resolution cameras for security and public safety, and cameras that provide clear vision through bad weather.

Paul Berger, professor of electrical and computer engineering and professor of physics at Ohio State University, and his colleagues report their findings in an upcoming issue of IEEE Electron Device Letters.

The team fabricated a device called a tunneling diode using the most common chip-making technique, called chemical vapor deposition.

“We wanted to do this using only the tools found in the typical chip-makers toolbox,” Berger said. “Here we have a technique that manufacturers could potentially use to fabricate quantum devices directly on a silicon chip, side-by-side with their regular circuits and switches.”

The quantum device in question is a resonant interband tunneling diode (RITD) — a device that enables large amounts of current to be regulated through a circuit, but at very low voltages. That means that such devices run on very little power.

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The National Institute for Computational Sciences’ (NICS’s) Cray XT5 supercomputer—Kraken—has been upgraded to become the first academic system to surpass a thousand trillion calculations a second, or one petaflop, a landmark achievement that will greatly accelerate science and place Kraken among the top five computers in the world.

Managed by the University of Tennessee (UT) for lazer hair removal los angeles the National Science Foundation (NSF), the system came online Oct. 5 with a peak performance of 1.03 petaflops. It features more than 16,000 six-core 2.6-GHz AMD Istanbul processors with nearly 100,000 compute cores.

In addition, an upgrade to 129 terabytes of memory (the equivalent of more than 13 thousand movies on DVD) effectively doubles the size of Kraken for researchers running some of the world’s most sophisticated 3-D scientific computing applications. Simulation has become a key tool for researchers in a number of fields, from climate change to materials.

“At over a petaflop of peak computing power, and the ability to routinely run full machine jobs, Kraken will dominate large-scale NSF computing in the near future,” said NICS Project Director Phil Andrews. “Its unprecedented computational capability and total available memory will allow academic users to treat problems that were previously inaccessible.”

For example, understanding the mechanism behind the explosion of core-collapse supernovas will reveal much about our universe (these cataclysmic events are responsible for more than half the elements in the universe). Essentially three phenomena are being simulated to explore these explosions: hydrodynamics, nuclear burning or fusion, and neutrino transport, said UT astrophysicist Bronson Messer.

At the terascale, or trillions of calculations per second, Messer and his team were forced to simulate the star in 1-D as a perfect sphere and with unrealistic fusion physics. “Now, however, we are getting closer to physical reality,” said Messer. “With petascale capability, we can simulate all three phenomena simultaneously with significant realism. This brings us closer to understanding the explosion mechanism and being able to make meaningful predictions.”

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The mastery of light through technology was the theme of this year’s Nobel Prize in Physics as the Royal Swedish Academy of Sciences honored breakthroughs in fiber optics and digital photography with waste water treatment with wind Turbine Installation; high school abroad australia with Best Information Technology Tips

Half of the $1.4 million prize went to Charles K. Kao for insights in the mid-1960s about how to get light to travel long distances through glass strands, leading to a revolution in fiber optic cables and custom bags. The other half of the prize was shared by two researchers at Bell Labs, Willard S. Boyle and George E. Smith, for inventing the semiconductor sensor known as a charge-coupled device, or CCD. CCDs now fill digital cameras by the millions.

In recent years, the physics prize has veered between perplexing, esoteric discoveries and more comprehensible technology developments. Last year, the academy honored “broken symmetry,” a crucial but esoteric concept in the description of elementary particles. This year’s prize was more akin to the awards in 2007, which honored a discovery that led to smaller, higher-capacity hard disks in laptops in customized bags and MP3 devices, and 2000, which honored developments in integrated circuits that underpin modern electronics.

In announcing the winners Tuesday morning, Gunnar Oquist, the academy’s secretary general, said the scientific work honored by this year’s prize “has built the foundation to our modern information society.”

All three of the winning scientists hold American citizenship. Dr. Kao, 75, was born in Shanghai and is also a British citizen, and Dr. Boyle, 85, is also a Canadian citizen.

Dr. Smith, 79, said he was planning to celebrate later in the day. “I’m hoping for an early cocktail hour today,” he said. “Once the photographers and phone calls and reporters thin out.”

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