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“It’s clear that the light is trapped — there are photons circulating around the atoms,” Everett says. “The atoms absorbed some of the trapped light, but a substantial proportion of the photons were frozen inside the atomic cloud.”

Co-researcher Geoff Campbell from ANU explained that while photons commonly pass by each other at the speed of light without any interactions, atoms interact with each other more freely.

“Corralling a crowd of photons in a cloud of ultra-cold atoms creates more opportunities for them to interact,” Campbell says.

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Remember that scene in “The Force Awakens” where the dark side warrior Kylo Ren stops a laser blast in mid-air? In a Canberra laboratory, physicists have managed a feat almost as magical: they froze the movement of light in a cloud of ultracold atoms. This discovery could help bring optical quantum computers from the realms of sci-fi to reality.

The experiment, published in a paper this week, was inspired by a computer stimulation run by lead researcher Jesse Everett from the Australian National University. The researchers used a vaporized cloud of ultracold rubidium atoms to create a light trap, into which they shone infrared lasers. The light trap constantly emitted and re-captured the light.

“It’s clear that the light is trapped – there are photons circulating around the atoms,” Everett says. “The atoms absorbed some of the trapped light, but a substantial proportion of the photons were frozen inside the atomic cloud.”

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Hmmm; like the graphic reminds of one of my posts.


In Brief.

  • Quantum computers would run some 100 million times faster than your PC, but they have proven to be a monumental feat of engineering.
  • In a new experiment, physicists managed to stop light, which helps us overcome challenges and brings us close to optical quantum computing.

A team of researchers at The Australian National University (ANU) may have found another work-around to bring us closer to quantum computing: The physicists have managed to find a new way to stop light.

Light was trapped by shining infrared lasers into ultra-cold atomic vapor. While the atoms absorbed some photons, a large amount were left in a frozen state in the atomic cloud — enhancing photon interaction with atoms or other photons.

Dramatic advances in laser technologies are enabling novel studies to explore laser-matter interactions at ultrahigh intensity. By focusing high-power laser pulses, electric fields (of orders of magnitude greater than found within atoms) are routinely produced and soon may be sufficiently intense to create matter from light.

Now, intriguing calculations from a research team at the Institute of Applied Physics of the Russian Academy of Sciences (IAP RAS), and reported this week in Physics of Plasmas, explain the production and dynamics of electrons and positrons from ultrahigh-intensity laser-matter interactions.

READ MORE ON AMERICAN INSTITUTE OF PHYSICS | AIP PUBLISHING

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Researchers at the Karlsruhe Institute of Technology say they have developed a quantum photonic circuit with an electrically driven light source. Described as a ‘complete quantum optical structure on a chip’, the development is said to fulfil one condition for the use of photonic circuits in optical quantum computers.

“Experiments investigating the applicability of optical quantum technology have often claimed whole laboratory spaces,” said Professor Ralph Krupke. “However, if this technology is to be employed meaningfully, it must be accommodated on a minimum of space.”

The light source for the quantum photonic circuit is carbon nanotubes which emit single particles of light when excited by a laser. Because they emit single photons, carbon nanotubes are attractive as light sources for optical quantum computers.

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A Primer for Deterministic Thermodynamics and Cryodynamics

Dedicated to the Founder of Synergetics, Hermann Haken

Otto E. Rossler, Frank Kuske, Dieter Fröhlich, Hans H. Diebner, Thimo Bo¨ hl, Demetris T. Christopoulos, Christophe Letellier

Abstract The basic laws of deterministic many-body systems are summarized in the footsteps of the deterministic approach pioneered by Yakov Sinai. Two fundamental cases, repulsive and attractive, are distinguished. To facilitate comparison, long-range potentials are assumed both in the repulsive case and in the new attractive case. In Part I, thermodynamics – including the thermodynamics of irreversible processes along with chemical and biological evolution – is presented without paying special attention to the ad hoc constraint of long-range repulsion.Otto E. Rossler In Part II, the recently established new fundamental discipline of cryodynamics, based on long-range attraction, is described in a parallel format. In Part III finally, the combination (“dilute hot-plasma dynamics”) is described as a composite third sister discipline with its still largely unknown properties. The latter include the prediction of a paradoxical “double-temperature equilibrium” or at least quasi-equilibrium existing which has a promising technological application in the proposed interactive local control of hot-plasma fusion reactors. The discussion section puts everything into a larger perspective which even touches on cosmology.
Keywords: Sinai gas, chaos theory, heat death, dissipative structures, second arrow, Point Omega, Super Life, paradoxical cooling, antifriction, paradoxical acceleration, Sonnleitner numerical instability, dilute-plasma paradigm, two-temperature equilibrium, ITER, MHD, interactive plasma cooling, McGuire reactor, Hubble law, Zwicky rehabilitated, Perlmutter-Schmidt-Riess wiggle, mean cosmic temperature, van Helmont, Lavoisier, Kant, Poincaré, double-faced Sonnleitner map. (August 26, 2016)

Otto E. Rossler, Frank Kuske, Dieter Fro¨ hlich, Thimo Bo¨ hl
Division of Theoretical Chemistry, University of Tübingen, Auf der Morgenstelle 18, 72076 Tu¨ bingen, Germany

Hans H. Diebner
Department of Medical Informatics, Technical University Dresden, Blasewitzerstr. 86,
01307 Dresden, Germany

Demetris T. Christopoulos
National and Kapodistrian University of Athens, Department of Economics, Sofokleous 1 str.,
10509 Athens, Greece

Christophe Letellier
Physics Department, University of Rouen CORIA, Avenue de l’Université, 76801 Saint-Étienne-du-Rouvray, France

Full paper: http://environmental-safety.webs.com/Deterministic_Thermo_Cryo.pdf

Now, intriguing calculations from a research team at the Institute of Applied Physics of the Russian Academy of Sciences (IAP RAS), and reported this week in Physics of Plasmas, from AIP Publishing, explain the production and dynamics of electrons and positrons from ultrahigh-intensity laser-matter interactions. In other words: They’ve calculated how to create matter and antimatter via lasers.

Strong electric fields cause electrons to undergo huge radiation losses because a significant amount of their energy is converted into gamma rays — high-energy photons, which are the particles that make up light. The high-energy photons produced by this process interact with the strong laser field and create electron-positron pairs. As a result, a new state of matter emerges: strongly interacting particles, optical fields, and gamma radiation, whose dynamics are governed by the interplay between classical physics phenomena and quantum processes.

A key concept behind the team’s work is based on the quantum electrodynamics (QED) prediction that “a strong electric field can, generally speaking, ‘boil the vacuum,’ which is full of ‘virtual particles,’ such as electron-positron pairs,” explained Igor Kostyukov of IAP RAS. “The field can convert these types of particles from a virtual state, in which the particles aren’t directly observable, to a real one.”

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When the quantum computer was imagined 30 years ago, it was revered for its potential to quickly and accurately complete practical tasks often considered impossible for mere humans and for conventional computers. But, there was one big catch: Tiny-scale quantum effects fall apart too easily to be practical for reliably powering computers.

Now, a team of scientists in Japan may have overcome this obstacle. Using laser light, they have developed a precise, continuous control technology giving 60 times more success than previous efforts in sustaining the lifetime of “qubits,” the unit that quantum computers encode. In particular, the researchers have shown that they can continue to create a known as the entangled state—entangling more than one million different physical systems, a world record that was only limited in their investigation by data storage space.

This feat is important because entangled quantum particles, such as atoms, electrons and photons, are a resource of created by the behaviors that emerge at the tiny quantum scale. Harnessing them ushers in a new era of information technology. From such behaviors as superposition and entanglement, quantum particles can perform enormous calculations simultaneously. The report of their investigation appears this week in the journal APL Photonics.

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Yesterday, in the New York Review of Books, Freeman Dyson analyzed a trio of recent books on humanity’s future in the larger cosmos. They were How to Make a Spaceship: A Band of Renegades, an Epic Space Race, and the Birth of Private Spaceflight; Beyond Earth: Our Path to a New Home in the Planets; and All These Worlds Are Yours: The Scientific Search for Alien Life.

Dyson is “a brilliant physicist and contrarian,” as the theoretical astrophysicist Lawrence Krauss recently told Nautilus. So I was waiting, as I read his review, to come across his profound and provocative pronouncement about these books, and it came soon enough: “None of them looks at space as a transforming force in the destiny of our species,” he writes. The books are limited in scope by looking at the future of space as a problem of engineering. Dyson has a grander vision. Future humans can seed remote environments with genetic instructions for countless new species. “The purpose is no longer to explore space with unmanned or manned missions, but to expand the domain of life from one small planet to the universe.”

Dyson can be just as final in his opinions on the destiny of scientific investigation. According to Krauss, Dyson once told him, “There’s no way we’re ever going to measure gravitons”—the supposed quantum particles underlying gravitational forces—“because there’s no terrestrial experiment that could ever measure a single graviton.” Dyson told Krauss that, in order to measure one, “you’d have to make the experiment so massive that it would actually collapse to form a black hole before you could make the measurement.” So, Dyson concluded, “There’s no way that we’ll know whether gravity is a quantum theory.”

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