Physicists Entangle Atoms Using Microwaves for the First Time

[American Patriot]

Physicists Entangle Atoms Using Microwaves for the First Time

K. Cameron Lau | Aug 11, 2011 | 2min:32sec Physicists Entangle Atoms Using Microwaves for the First Time. Physicists at the National Institute of Standards and Technology have for the first time linked the quantum properties of two separate ions by manipulating them with microwaves instead of the usual laser beams. The breakthrough may ultimately lead to what researchers are calling smartphone-sized quantum computers that would replace existing room-sized quantum computing, quote “laser parks,” through the exploitation of the commercial microwave technology.

[American Patriot]

Let me help you all out. Here's an older article (2007) with a bit more information about what this truly means...

Single-atom entanglement goes further

Sep 6, 2007 1 comment
Physicists in the US have managed to entangle two individual atomic ions that are one metre apart. Their system, which is the first to uses photons to remotely entangle a pair of atomic ions, could pave the way for the construction of practical quantum information networks (Nature 449 68).
Unlike classical bits of information, which must take either the value 0 or 1, quantum bits or “qubits” can assume a mixed-up superposition of the values 0 and 1. Furthermore, two qubits can be entangled so that the value of one qubit is revealed by measuring the value of the other. Although these odd properties have spawned an array of applications such as quantum encryption, future devices will hinge on the ability to remotely entangle qubits in a network that have already been separated by large distances.
Ideally atoms would be used to store qubits because they would remain stable over long timescales, while photons -- which can travel undisturbed over long distances -- would entangle them. Now Chris Monroe from the University of Maryland and others from the University of Michigan have demonstrated that photons emitted towards each other from separated atomic qubits can -- after they have met midway -- entangle the qubits from afar.
In their experiment, two atomic ions trapped a metre apart by electric fields are excited into a higher energy state using a pulse of laser light. Moments later, each ion falls back into one of two distinct energy states while emitting a photon of a corresponding frequency that can show what the new state is. Both of these photons are captured by a lens and guided towards each other along fibre optics.
At the ends of the fibres the photons meet at a beamsplitter, and if they are the same frequency they interfere. Monroe and co-workers can then detect the photons at the two outputs of the beamsplitter, from which they learn what the atomic states are. However, because they cannot know what ions these states belong to, the ions are left in a superposition of the two possibilities -- in other words, they are left entangled.

The Michigan team can prove this entanglement exists by using another laser to probe the two ions, which fluoresce differently depending on their state, for signs of correlations. Over many experiment runs, they found that the correlations persisted, even when the ions were “rotated” to satisfy all the statistical conditions. “Useful entanglement of such states of matter has never been established before over such a distance,” Monroe told physicsworld.com.
The system may not have practical applications just yet, however. The losses in the apparatus conspire to produce an entanglement probability of about 10^-9, meaning the researchers only get a successful entanglement every few minutes despite repeating the process a million times a second. Moreover, the near-UV photons required are of high loss in optical fibre, which limits the system’s long-distance potential. “We are looking at the possibility of efficiently converting these photons to more friendly -- or even telecom -- wavelength, where they could safely go many kilometres,” Monroe said.

[American Patriot]

And another one:

Spooky Atomic Clocks


Spooky Atomic Clocks

NASA-supported researchers hope to improve high-precision clocks by entangling their atoms.

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January 23, 2004: Einstein called it "spooky action at a distance." Now NASA-funded researchers are using an astonishing property of quantum mechanics called "entanglement" to improve atomic clocks--humanity's most precise way to measure time. Entangled clocks could be as much as 1000 times more stable than their non-entangled counterparts.
This improvement would benefit pilots, farmers, hikers--in short, anyone who uses the Global Positioning System (GPS). Each of the 24+ GPS satellites carries four atomic clocks on board. By triangulating time signals broadcast from orbit, GPS receivers on the ground can pinpoint their own location on Earth
Right: Quantum entanglement does some mind-bending things. In this laser experiment entangled photons are teleported from one place to another.
NASA uses atomic clocks for spacecraft navigation. Geologists use them to monitor continental drift and the slowly changing spin of our planet. Physicists use them to check theories of gravity. An entangled atomic clock might keep time precisely enough to test the value of the Fine Structure Constant, one of the fundamental constants of physics.

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"The ability to measure time with very high precision is an invaluable tool for scientific research and for technology," says Alex Kuzmich, a physicist at the Georgia Institute of Technology. Through its office of Biological and Physical Research, NASA recently awarded a grant to Kuzmich and his colleagues to support their research. Kuzmich has studied quantum entanglement for the last 10 years and has recently turned to exploring how it can be applied to atomic clocks.
Particles entwined
Einstein never liked entanglement. It seemed to run counter to a central tenet of his theory of relativity: nothing, not even information, can travel faster than the speed of light. In quantum mechanics, all the forces of nature are mediated by the exchange of particles such as photons, and these particles must obey this cosmic speed limit. So an action "here" can cause no effect "over there" any sooner than it would take light to travel there in a vacuum.
But two entangled particles can appear to influence one another instantaneously, whether they're in the same room or at opposite ends of the Universe. Pretty spooky indeed.
Quantum entanglement occurs when two or more particles interact in a way that causes their fates to become linked: It becomes impossible to consider (or mathematically describe) each particle's condition independently of the others'. Collectively they constitute a single quantum state.
Left: Making a measurement on one entangled particle affects the properties of the other instantaneously. Image by Patrick L. Barry.
Two entangled particles often must have opposite values for a property -- for example, if one is spinning in "up" direction, the other must be spinning in the "down" direction. Suppose you measure one of the entangled particles and, by doing so, you nudge it "up." This causes the entangled partner to spin "down." Making the measurement "here" affected the other particle "over there" instantaneously, even if the other particle was a million miles away.

While physicists and philosophers grapple with the implications for the nature of causation and the structure of the Universe, some physicists are busy putting entanglement to work in applications such as "teleporting" atoms and producing uncrackable encryption.
Atomic clocks also stand to benefit. "Entangling the atoms in an atomic clock reduces the inherent uncertainties in the system," Kuzmich explains.
At the heart of every atomic clock lies a cloud of atoms, usually cesium or rubidium. The natural resonances of these atoms serve the same purpose as the pendulum in a grandfather clock. Tick-tock-tick-tock. A laser beam piercing the cloud can count the oscillations and use them to keep time. This is how an atomic clock works.
Right: Lasers are a key ingredient of atomic clocks--both the ordinary and entangled variety. Click on the image to learn more.
"The best atomic clocks on Earth today are stable to about one part in 10¹⁵," notes Kuzmich. That means an observer would have to watch the clock for 10¹⁵ seconds or 30 million years to see it gain or lose a single second.
The precision of an atomic clock depends on a few things, including the number of atoms being used. The more atoms, the better. In a normal atomic clock, the precision is proportional to the square-root of the number of atoms. So having, say, 4 times as many atoms would only double the precision. In an entangled atomic clock, however, the improvement is directly proportional to the number of atoms. Four times more atoms makes a 4-times better clock.
Using plenty of atoms, it might be possible to build a "maximally entangled clock stable to about one part in 10¹⁸," says Kuzmich. You would have to watch that clock for 10¹⁸ seconds or 30 billion years to catch it losing a single second.
Kuzmich plans to use the lasers already built-in to atomic clocks to create the entanglement.
"We will measure the phase of the laser light passing through the cloud of atoms," he explains. Measuring the phase "tweaks the laser beam," and if the frequency of the laser has been chosen properly, tweaking the beam causes the atoms to become entangled. Or, as one quantum physicist might say to another, "such a procedure amounts to a quantum non-demolition (QND) measurement on the atoms, and results in preparation of a Squeezed Spin State."
Above: Georgia Institute of Technology professor of physics Alex Kuzmich.
How soon an entangled clock could be built--much less launched into space aboard a hypothetical new generation of GPS satellites--is difficult to predict, cautions Kuzmich. The research is still at the stage of just demonstrating the principle. Building a working prototype is probably several years away.

But thanks to research such as this, having still-better atomic clocks available to benefit science and technology is only a matter of time.

Web Links

Tick-Tock Atomic Clock -- (Science@NASA) Scientists are building atomic clocks that keep time with mind-boggling precision. Such devices will help farmers, physicists, and interstellar travelers alike.
Prof. Alex Kuzmich -- Georgia Tech professor of physics. His atomic clock research team includes Ryan Smith and Dmitry Matsukevich.
NASA's Office of Biological and Physical Research supports studies of fundamental physics for the benefit of people on Earth and in space.
What is an atomic second?In an atomic clock, the steady "tick" of an electronic oscillator is kept steady by comparing it to the natural frequency of an atom -- usually cesium-133. When a cesium atom drops from one particular energy level to another, a microwave photon emerges. The wave-like photon oscillates like a pendulum in an old-style clock. When it has oscillated precisely 9,192,631,770 times -- by decree of the Thirteenth General Conference on Weights and Measures in 1967 -- we know that one "atomic second" has elapsed.

[American Patriot]

Basically for those of you not into physics, this means a few things that are very important to science.

First off all, we're talking "quantum" computers.

Secondly we're talking perhaps of "instantaneous communications" - something very similar to what they called "Tachyon communications" (on Star Trek) which went faster than the speed of light waves.

Finally, we're talking the ability to teleport matter vast distances.

Although, we're not talking about any of this stuff being useful any time soon, we have actually scratched the surface of things like "matter transporters", "faster than light communications" and "quantum computing" that will take computers to speeds we can't even imagine within about 100 years.

We will certainly double out knowledge in a decade on this, and double it yet again in another decade.

The things we've looked at over the past few months on other parts of the forum, for instance how space travel might appear in the future (and I believe it was Malsua who said something to the effect that things will be so different in 100 years we won't recognize it) will be so vastly different then than now that none of us alive now would recognize things.

100 years ago you could at least guess.

Today, we can't guess what 100 years into the future will be like.

And if our society continues on the path we're on though, we will look more like Babylon soon enough and all this work and learning will be lost to future generations.