Another step toward quantum computers: Using photons for memory

Mar 29, 2013 by Eric Gershon
Another step toward quantum computers: Using photons for memory
Scientists at Yale University have found a new way to manipulate microwave signals that could aid the long-term effort to develop a quantum computer.

(Phys.org) —Scientists at Yale University have found a new way to manipulate microwave signals that could aid the long-term effort to develop a quantum computer, a powerful tool that would revolutionize information processing through unprecedented speed and power.

Like regular (classical) computers, quantum computers must be able to receive, store, and manipulate information in order to perform calculations. But the fragile nature of quantum information—which exists as a "0" or "1" or both simultaneously—poses challenges. In research published March 14 in the journal Nature, Yale physicists report an advance in developing memory mechanisms.

The advance involves photons, the smallest units of microwave signals, which can serve as a quantum computer's memory, like the RAM of a regular computer. Photons can carry and hold quantum information for a long time, because they interact weakly with the media they typically travel through—coaxial cables, wires, or air, for example. The weakness of these interactions prevents the photons from being absorbed by the medium and preserves the quantum information, once it's been encoded.

In the Nature paper, the researchers report creating an in which photons repel photons, allowing for efficient, non-destructive encoding and manipulation of quantum information.

"Our experiment has shown that we can create a medium that on the one hand enables us to manipulate the photon state, and on the other hand does not absorb the , which would destroy the stored in them," said Gerhard Kirchmair, a postdoctoral researcher at Yale and the paper's lead author. "This creates a source for novel quantum states without the need for complicated control techniques and could simplify certain quantum computation algorithms. In the long run it could be used as one of the many resources required to build a quantum computer."

The medium consists of a superconducting qubit coupled to a microwave cavity resonator.

Robert J. Schoelkopf, a professor of applied physics and physics at Yale, led the research team.

The paper, titled "Observation of collapse and revival due to the single-photon Kerr effect," contains a complete list of co-authors.

"The tricky bit for future experiments will be to switch on and off this effect at will, so that it only happens if we want it to happen," said Kirchmair. "We already have experiments on the way that show that we can do that."

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vacuum-mechanics
1 / 5 (6) Mar 29, 2013
The paper, titled "Observation of quantum state collapse and revival due to the single-photon Kerr effect," contains a complete list of co-authors.
"The tricky bit for future experiments will be to switch on and off this effect at will, so that it only happens if we want it to happen," said Kirchmair. "We already have experiments on the way that show that we can do that."

This seems to be another success practical work in quantum ream, in contrast to the theoretical work in which nowadays we still could not understand the mystery basic foundation of quantum mechanics! Maybe this physical mechanism could help the matter.
http://www.vacuum...19〈=en
vlaaing peerd
5 / 5 (1) Mar 29, 2013
Maybe this physical mechanism could help the matter.

Or not.

Tektrix
5 / 5 (1) Mar 29, 2013
"could not understand the mystery basic foundation"

With a mystery foundation of quantum bricks,
I learned early-on what makes the world tick.
Waves have functions that collapse on a beach,
made of eyes and meters
and labs full of geeks.

We feel the weight of solid matter,
measure heat, and see light scatter.
Held checked by relativity,
the speed of light,
and gravity.

What underpins reality
is something quite unreal it seems;
A quantized playground dug around
by stellar children
in their dreams.

Thanks for the inspiration, VM ;)
Ober
5 / 5 (1) Mar 29, 2013
@Vacuum, PLEASE stop with the same post on every article!!!!!! It only serves to piss people off!!!!

Now back to normal stuff, how does a photon "repel" another photon??
Velasco
not rated yet Mar 29, 2013
This stuff is confusing. I need to take more classes.
Tektrix
5 / 5 (1) Mar 29, 2013
This stuff is confusing. I need to take more classes.

http://arxiv.org/abs/1211.2228 for the pre-print. The paper is dense but not entirely inaccessible to those with some understanding of fundamental quantum mechanics. This physorg article misses a great deal of the actual work, which is as experimentally impressive as it is theoretically accurate.
Higgsbengaliboson
not rated yet Mar 30, 2013
Actually this particular research was carried out in last November which has been published in Nature journal.There are several techniques in quantum computing(i.e optical,adiabatic etc) and this one is one of the most feasible one.

For more detail follow twitter #QuantumComputing
ValeriaT
1 / 5 (2) Mar 30, 2013
BTW This article makes pretty obvious, that the time evolution equation of Wigner function is the quantum analogue version of Feynman diagrams.
brt
1 / 5 (1) Apr 02, 2013
BTW This article makes pretty obvious, that the time evolution equation of Wigner function is the quantum analogue version of Feynman diagrams.


I see you've tried to mash together 2 things you know nothing about in an attempt to make it sound like you have an idea of what you're talking about. Maybe it'll work next time.
brt
1 / 5 (1) Apr 02, 2013
Maybe this physical mechanism could help the matter.

Or not.



I hate the guy so much because he's just so hopelessly pathetic. It's like a drug addict who just can't stop.