Archive for the ‘quantum physics’ category: Page 489

Oct 9, 2015

Scientists paint quantum electronics with beams of light

Posted by in categories: computing, electronics, materials, quantum physics

A team of scientists from the University of Chicago and the Pennsylvania State University have accidentally discovered a new way of using light to draw and erase quantum-mechanical circuits in a unique class of materials called topological insulators.

In contrast to using advanced nanofabrication facilities based on chemical processing of materials, this flexible technique allows for rewritable ‘optical fabrication’ of devices. This finding is likely to spawn new developments in emerging technologies such as low-power electronics based on the spin of electrons or ultrafast quantum computers.

The research is published today in the American Association for the Advancement of Science’s new online journal Science Advances, where it is featured on the journal’s front page.

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Oct 8, 2015

Scientists float new approach to creating computer memory

Posted by in categories: computing, quantum physics

What can skyrmions do for you? These ghostly quantum rings, heretofore glimpsed only under extreme laboratory conditions, just might be the basis for a new type of computer memory that never loses its grip on the data it stores.

Now, thanks to a research team including scientists from the National Institute of Standards and Technology (NIST), the exotic ring-shaped magnetic effects have been coaxed out of the physicist’s deepfreeze with a straightforward method that creates magnetic skyrmions under ambient room conditions. The achievement brings skyrmions a step closer for use in real-world data storage as well as other novel magnetic and electronic technologies.

If you have a passing familiarity with particle physics, you might expect skyrmions to be particles; after all, they sound a lot like fermions, a class of particles that includes protons and neutrons. But skyrmions are not fundamental pieces of matter (not even of yogurt); they are effects named after the physicist who proposed them. Until just recently, magnetic skyrmions had only been seen at very low temperatures and under powerful magnetic fields.

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Oct 8, 2015

Entanglement: Gravity’s long-distance connection

Posted by in categories: computing, cosmology, quantum physics

Many researchers find these ideas irresistible. Within the last few years, physicists in seemingly unrelated specialties have converged on this confluence of entanglement, space and wormholes. Scientists who once focused on building error-resistant quantum computers are now pondering whether the universe itself is a vast quantum computer that safely encodes spacetime in an elaborate web of entanglement. “It’s amazing how things have been progressing,” says Van Raamsdonk, of the University of British Columbia in Vancouver.

Physicists have high hopes for where this entanglement-spacetime connection will lead them. General relativity brilliantly describes how spacetime works; this new research may reveal where spacetime comes from and what it looks like at the small scales governed by quantum mechanics. Entanglement could be the secret ingredient that unifies these supposedly incompatible views into a theory of quantum gravity, enabling physicists to understand conditions inside black holes and in the very first moments after the Big Bang.

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Oct 7, 2015

Can quantum physics explain irrational decisions? — By Leslie D’Monte | Livemint

Posted by in category: quantum physics


“Thinking in a quantum-like way lets people confront complex questions.”

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Oct 6, 2015

Crucial hurdle overcome in quantum computing

Posted by in categories: computing, quantum physics

The significant advance, by a team at the University of New South Wales (UNSW) in Sydney appears today in the international journal Nature.

“What we have is a game changer,” said team leader Andrew Dzurak, Scientia Professor and Director of the Australian National Fabrication Facility at UNSW.

“We’ve demonstrated a two-qubit logic gate — the central building block of a quantum computer — and, significantly, done it in . Because we use essentially the same device technology as existing computer chips, we believe it will be much easier to manufacture a full-scale processor chip than for any of the leading designs, which rely on more exotic technologies.

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Oct 5, 2015

Australian engineers just built a quantum logic gate in silicon for the first time

Posted by in categories: computing, materials, particle physics, quantum physics

For decades, researchers have been trying to build a computer that harnesses the enormous potential of quantum mechanics. Now engineers from the University of New South Wales (UNSW) in Australia have overcome the final hurdle, by creating a quantum logic gate in silicon — the same material that today’s computer chips are made from.

The newly developed device allows two quantum bits — or qubits — to communicate and perform calculations together, which is a crucial requirement for quantum computers. Even better, the researchers have also worked out how to scale the technology up to millions of qubits, which means they now have the ability to build the world’s first quantum processor chip and, eventually, the first silicon-based quantum computer.

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Oct 5, 2015

A quantum logic gate in silicon built for the for the first time (w/video)

Posted by in categories: computing, encryption, quantum physics, supercomputing

A Game Changer in Quantum Computing:
The ingredients for superfast computers could be nearly in place. For the first time, researchers have demonstrated that two silicon transistors acting as quantum bits can perform a tiny calculation.

The advance represents the final physical component needed to realise the promise of super-powerful silicon quantum computers, which harness the science of the very small — the strange behaviour of subatomic particles — to solve computing challenges that are beyond the reach of even today’s fastest supercomputers. Potentially transforming fields like encryption and the search for new pharmaceuticals.

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Oct 4, 2015

Spooky Quantum Action Might Hold the Universe Together

Posted by in categories: quantum physics, space

Caption: Tensor networks could connect space-time froth to quantum information. Hannes Hummel for Quanta Magazine.

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Oct 4, 2015

Signals from empty space

Posted by in category: quantum physics

What are the properties of the vacuum, the absolute nothingness? So far, physicists have assumed that it is impossible to directly access the characteristics of the ground state of empty space. Now, a team of physicists led by Prof. Alfred Leitenstorfer at the University of Konstanz (Germany) has succeeded in doing just that. They demonstrated a first direct observation of the so-called vacuum fluctuations by using short light pulses while employing highly precise optical measurement techniques. The duration of their light pulses was ensured to be shorter than half a cycle of light in the spectral range investigated. According to quantum physics, these oscillations exist even in total darkness, when the intensity of light and radio waves completely disappears. These findings are of fundamental importance for the development of quantum physics and will be published in the journal Science; an advance online version has appeared on October 1, 2015.

The existence of vacuum fluctuations is already known from theory as it follows from Heisenberg’s uncertainty principle, one of the main pillars of quantum physics. This principle dictates that electric and magnetic fields can never vanish simultaneously. As a consequence, even total darkness is filled with finite fluctuations of the electromagnetic field, representing the quantum ground state of light and radio waves. However, until now direct experimental proof of this basic phenomenon has been considered impossible. Instead, it is usually assumed that vacuum fluctuations are manifested in nature only indirectly. From spontaneous emission of light by excited atoms e.g. in a fluorescent tube to influences on the structure of the universe during the Big Bang: these are just some of the instances that highlight the ubiquitous role the concept of vacuum fluctuations plays in the modern physical description of the world.

An experimental setup to measure electric fields with extremely high temporal resolution and sensitivity has now made it possible to directly detect vacuum fluctuations, despite all contrary assumptions. World-leading optical technologies and ultrashort pulsed laser systems of extreme stability provide the know-how necessary for this study. The research team at the University of Konstanz developed these technologies in-house and also an exact description of the results based on quantum field theory. The temporal precision achieved in their experiment is in the femtosecond range — a millionth of a billionth of a second. The sensitivity is limited only by the principles of quantum physics. “This extreme precision has enabled us to see for the first time that we are continuously surrounded by the fields of electromagnetic vacuum fluctuations” sums up Alfred Leitenstorfer.

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Oct 2, 2015

Google, NASA using quantum computing to push A.I., machine learning

Posted by in categories: computing, quantum physics, robotics/AI, space

Google and NASA are continuing to test quantum computers and this week entered into a new agreement to work with a series of updated systems.

D-Wave Systems, a quantum computing company based in Burnaby, British Columbia, announced this week that it had signed a deal to install a succession of D-Wave systems at NASA’s Ames Research Center in Moffett Field, California. NASA and Google on Wednesday also confirmed the deal.

NASA and the Universities Space Research Association (USRA) are collaborating on the project, which is focused on advancing artificial intelligence and machine learning.

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