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Encryption systems that rely on the “spooky” properties of quantum mechanics have long been hyped as the ultimate in spy- and hack-proof communication, and recently governments and large companies have begun sampling early examples of the technology. Now, scientists in Vienna have demonstrated a commercial telecommunications network protected by quantum cryptography, and say the system could be generally available in less than 10 years.

One of the researchers who worked out the basic idea behind quantum cryptography 25 years ago, Gilles Brassard, was on hand in Vienna to explain the mechanism. “All quantum security schemes are based on the Heisenberg Uncertainty Principle, on the fact that you cannot measure quantum information without disturbing it,” he explained. “Because of that, one can have a communications channel between two users on which it’s impossible to eavesdrop without creating a disturbance. An eavesdropper would create a mark on it. That was the key idea” [BBC News].

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Researchers at the University of California, Berkeley, announced yesterday that they were able to construct a prism that bent light “the wrong way” and so would make an object appear to vanish [Times UK]. Details of the two different experiments will be published separately later this week in Nature and Science.

To bend the light, the scientists used “metamaterials,” mixtures of metal and circuit board materials such as ceramic, Teflon or fiber composite [AP]. One group built what they called a metal “fishnet” of alternating silver and magnesium fluoride; the other used tiny silver nanowires. Both created negative refraction: Light is neither absorbed nor reflected by the objects, passing “like water flowing around a rock,” according to the researchers. As a result, only the light from behind the objects can be seen [BBC].

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The mechanism that triggers the colorful auroras that dance across the night sky near the Earth’s two poles has been revealed by a quintet of NASA satellites. Scientists already knew that disturbances in the Earth’s magnetic field, called “substorms,” bring charged particles into the Earth’s upper atmosphere, where they collide with gas particles. Those gas particles then release energy as light, which flickers across the sky in waves of greens, reds, and blues.

Now, researchers with NASA’s THEMIS mission say they’ve discovered what sets off those magnetic disturbances. The substorms begin far out in space, roughly a third of the way to the Moon, where magnetic fields from the Earth are thrown together and reconnect to sling charged particles back toward the planet, they say [New Scientist].

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Coating an ordinary sheet of glass with dye could be the key to cheaper, more efficient solar panels, according to a new study. Researchers say the dye absorbs visible light and transmits it to the edges of the glass sheet, where strips of photovoltaic cells convert the light into electricity.

Current solar panels are made entirely of the expensive photovoltaic cells. The team, from the Massachusetts Institute of Technology (MIT), claims the technology could slash the cost of generating electricity from sunlight, making it more competitive with standard grid power [The Guardian]. Although this technique is highly experimental, researchers say that eventually the collectors might double as windows… or could be used in place of standard solar panels [New Scientist].

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