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Hacker attacks on everything from social media accounts to government files could be largely prevented by the advent of quantum communication, which would use particles of light called “photons” to secure information rather than a crackable code.


Using light to send information is a game of probability: Transmitting one bit of information can take multiple attempts. The more photons a light source can generate per second, the faster the rate of successful information transmission.

“A source might generate a lot of photons per second, but only a few of them may actually be used to transmit information, which strongly limits the speed of quantum communication,” Bogdanov said.

For faster quantum communication, Purdue researchers modified the way in which a light pulse from a laser beam excites electrons in a man-made “defect,” or local disturbance in a crystal lattice, and then how this defect emits one photon at a time.

Researchers at the US Department of Energy’s (DOE’s) Oak Ridge National Laboratory (ORNL) has developed and tested a new #Interferometer


January 3, 2019 — By analyzing a pattern formed by the intersection of two beams of light, researchers can capture elusive details regarding the behavior of mysterious phenomena such as gravitational waves. Creating and precisely measuring these interference patterns would not be possible without instruments called interferometers.

For over three decades, scientists have attempted to improve the sensitivity of interferometers to better detect how the number of photons—particles that make up visible light and other forms of electromagnetic energy—leads to changes in light phases. Attempts to achieve this goal are often hampered by optical loss and noise, both of which can decrease the accuracy of interferometer measurements.

But now a team of researchers at the US Department of Energy’s (DOE’s) Oak Ridge National Laboratory (ORNL) has developed and tested a new interferometer to study the factors that contribute to these conditions, and they have devised solutions to overcome them. Their findings were published in the journal Applied Physics Letters, which promoted their paper to Editors’ Pick status. The editors award this distinction to noteworthy publications compiled in an exclusive list.

High-energy X-ray beams and a clever experimental setup allowed researchers to watch a high-pressure, high-temperature chemical reaction to determine for the first time what controls formation of two different nanoscale crystalline structures in the metal cobalt. The technique allowed continuous study of cobalt nanoparticles as they grew from clusters including tens of atoms to crystals as large as five nanometers.

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Get ready to get excited about excitons.

Excitons are quirky quasiparticles that exist only in semiconducting and insulating materials. Recently, a team of researchers in Lausanne, Switzerland discovered a way to control how excitons flow. Not only that, they also discovered new properties of the particles which they claim could lead to a new generation of electronic devices with transistors that lose less energy as heat. The results of their study were published this week in the journal Nature Photonics.

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Rice University physicists have created the world’s first laser-cooled neutral plasma, completing a 20-year quest that sets the stage for simulators that re-create exotic states of matter found inside Jupiter and white dwarf stars.

The findings are detailed this week in the journal Science and involve new techniques for cooling clouds of rapidly expanding to temperatures about 50 times colder than deep space.

“We don’t know the practical payoff yet, but every time physicists have laser cooled a new kind of thing, it has opened a whole world of possibilities,” said lead scientist Tom Killian, professor of physics and astronomy at Rice. “Nobody predicted that laser cooling atoms and ions would lead to the world’s most accurate clocks or breakthroughs in quantum computing. We do this because it’s a frontier.”

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The Cray-1 supercomputer, the world’s fastest back in the 1970s, does not look like a supercomputer. It looks like a mod version of that carnival ride The Round Up, the one where you stand, strapped in, as it dizzies you up. It’s surrounded by a padded bench that conceals its power supplies, like a cake donut, if the hole was capable of providing insights about nuclear weapons.

After Seymour Cray first built this computer, he gave Los Alamos National Laboratory a six-month free trial. But during that half-year, a funny thing happened: The computer experienced 152 unattributable memory errors. Later, researchers would learn that cosmic-ray neutrons can slam into processor parts, corrupting their data. The higher you are, and the bigger your computers, the more significant a problem this is. And Los Alamos—7,300 feet up and home to some of the world’s swankiest processors—is a prime target.

The world has changed a lot since then, and so have computers. But space has not. And so Los Alamos has had to adapt—having its engineers account for space particles in its hard- and software. “This is not really a problem we’re having,” explains Nathan DeBardeleben of the High Performance Computing Design group. “It’s a problem we’re keeping at bay.”

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On his 125th birth anniversary, ThePrint celebrates one of India’s greatest physicists.

New Delhi: Bose-Einstein statistics, Bose-Einstein Condensate, Bosons — these are terms that even casual observers of physics have heard regardless of whether they actually know about them or not. These nomenclatures, based upon Satyendra Nath Bose’s surname (along with Einstein’s in the first two cases), both commemorate and signify his immense contribution to physics.

Bose’s novel derivation of Planck’s formula without relying upon classical electrodynamics resolved a conceptual inconsistency which had troubled all famous scientists of the day.

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Researchers from MIT and elsewhere have recorded, for the first time, the “temporal coherence” of a graphene qubit—meaning how long it can maintain a special state that allows it to represent two logical states simultaneously. The demonstration, which used a new kind of graphene-based qubit, represents a critical step forward for practical quantum computing, the researchers say.

Superconducting quantum bits (simply, qubits) are artificial atoms that use various methods to produce bits of quantum information, the fundamental component of quantum computers. Similar to traditional binary circuits in computers, qubits can maintain one of two states corresponding to the classic binary bits, a 0 or 1. But these qubits can also be a superposition of both states simultaneously, which could allow quantum computers to solve complex problems that are practically impossible for traditional computers.

The amount of time that these qubits stay in this superposition state is referred to as their “coherence time.” The longer the coherence time, the greater the ability for the qubit to compute complex problems.

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