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First 'Quantum Computer Chips' Demonstrated
holy_calamity writes "The first quantum computer chips have been made by two US groups, New Scientist reports. Both NIST and Yale have demonstrated chips where information was transferred between two superconducting qubits using a 'quantum bus'. The bus is made from a cavity that traps a single microwave photon as a standing wave — the NIST group also managed to use the bus to store data from one qubit for a short time. 'After encoding information in one qubit, they transferred it into the cavity for 10 nanoseconds before transferring it to the other qubit. Yale's chip used qubits around 1-micron square built on silicon, while NIST used larger 10-square-micron qubits on top of sapphire. In both prototypes, the bus between the qubits was between five and seven millimeters long.'"
maybe I'm first, maybe I'm not.
Is it just me, or do you hate it when people say "Is it just me..."?
Must...Not...Imagine....Beowulf...Cluster....
Gifts for Geeks - Stuff that really matters!
Howdy. I don't claim to understand all of this. However, the more I read, the more I am convinced the universe makes no sense. I am waiting for the guy who is dreaming all of this to wake up and for all of us to stop existing.
See my journal for slashdot ID's by year. Mine created in 2005. http://slashdot.org/journal/289875/slashdot-ids-by-year
Personally, I'm holding out for the first Quantum Whizzer.
Don't let your cat get inside it!
He may or may not survive it.
Knowledge is power. Knowledge shared is power lost.
I was going to tell you, but I changed the outcome by reading it!
Well, back to rejecting software patent applications.
... but will it run Linux? (Or will it run and not run Linux at the same time?)
You can't know how many cats wide it is or fast it is until you transfer data over it.
This has got to be an awesome project to work on...I'm jealous.
Yeah? Well I think you're overrated too.
that stuff like this is the "glue" behind the universe, and someday, some scientist in a lab is going to have an experiment go horribly wrong?
.. know anybody in Hollywood?
Every time you ________ in Soviet Russia, kitten kills God!
Once quantum computers become mainstream, what will we use for encryption? Are there algorithms that are computable by standard computers but are also unbreakable using quantum computers?
-Bucky
"What's a cubit?"
Intel Core 2 Duo die size is 143mm^2, so that's 143 million devices. That is somewhere between Barton and the K-8 (also above the Itanium, but nowhere near the I2). Ref: http://en.wikipedia.org/wiki/Transistor_count If you truely can do parallel processing then I suppose it could replace Si.
My understanding is quantum entanglement cannot be used to transfer information.
Well, it has never been successfully tested.
Just pure speculation on my part - but I believe you need a "common carrier" of some sort of wave to setup entanglement. It makes sense to build this into a chip so that you can alter the setup at run time.
I said no... but I missed and it came out yes.
This doesn't make sense to me cuz I'm not a quantum physicist. If the qubits are in two states at the same time, how do you determine that the data was transfered and stored on the second qubit like that said? Wouldn't it always appear the same because it's always in both states at once?
Google's Super Secret Search Algorithm: SELECT @search_results FROM internet WHERE @search_results = 'good'
change the outcome of the story?
Well, there were two devices. I was assuming one had a bus 5mm long, and the other had a bus 7mm long.
I read the internet for the articles.
Yes, D-Wave's device is on a chip, but there are others long before that, too. I am not sure what the first solid-state qubit experiment was, but such experiments have been going on since the late 90's. The claim of these experiments is that they demonstrate the first quantum bus on a chip.
Readers may find the Yale group's press release interesting.
In other news, the NSA is partnering with NIST and University of Maryland to form the Joint Quantum Institute.
Slashdot's first reaction to VMware
The one time pad, where the key length = message length is still safe as long as you never reuse the key. (the "one time" in one time pad.
As simple proof of this is that for any encrypted text of length N, there exists a key also of length N that will decrypt the etext to any plain text of length N. Therefore there is no way for an attacker to determine if an attempted key is valid or not. There if an attacker were to try every single key of length N, which is possible on some super large future quantum computer, all he will get out is every single decryption of length N, with no way to determine which is correct.
Suppose the plain text was "attack at dawn" and the etext was "xbdhgfhwteriur". After the attacker used his q-computer he'd have "attack at dawn", "attach at noon" and "attack at fred", along with 64 quintillion other combinations.
All ideas^H^H^H^H^Hprocesses in this post are Patent Pending. (as well as the process of patenting all postings)
Does it runs Halo 3?
Forget what I said in my , I misread your post. But for RSA and other public key algorithms, the speedup is exponential, so they're effectively defeated by QC. Grover's algorithm is just a quadratic speedup, so it can be defeated by doubling the key size.
The AACS key is NOT 0xF606EEFD628B1CA427BEA93A9CA9773F
Entanglement can't be used to communicate useful information.
Fun with Anagarams! LADS HOST, SHALT DOS. HAS DOLTS. AD SLOTHS, HATS SOLD. ASS HO, LTD.
...it was transferred to Q*bert and he jumped on one of those purple snakes.
Yes, because new things should have existing applications. They're new, they enable new. It might not have applicability now, but it might do when google offloads your search to a qbit coprocessor.
It's a good thing Tesla didn't feel the same way about A/C electricity.
The funky thing about fundamental and 'useless' physics research is that from time to time extremely interesting things come out of it.
Imagine if people could produce things as hard as diamond as easily and costless as they produce things of metal today. But that the material you use is rather a random pile of wood chips rather than ore mined out of the ground. Without fundamental research it is never ever going to happen, with it - it's more likely to than not.
Old Man Bradbury had been a fixture on the block for years. Every day he sat on his porch, rocking back in forth, idling smoking his pipe, and glaring at the world as it passed him by.
"So what?" he'd used to say when his neighbors would get a new car, "Is that going to get you anywhere any faster in this traffic?"
"So what?" he'd say when they put a man on the moon, "Am I going to live on the moon now? No? Then so what?"
New trends and fashions would pass him by, always receiving the two word response "So what?" There wasn't much that escaped his scoffing attitude, even his children.
"So what?" he said when presented with a flower from his daughter Noreen. "I can get those at the store, what, are you a florist now?"
"So what?" he told his son Billy as he brought home the second place trophy from little league, "someone else did a better job. Why even have a trophy for second?"
His work, his life, and his family dulled him. Nothing impressed him. The news was always the same, the new miracles of the modern age changing nothing other than how people waste their time. To Old Man Bradbury the world was a cold, static place, and if anything mattered to him it was making sure that everyone knew nothing did.
And so he lived on, rocking in place and watching the world from his porch, until one day the rocking stopped for good.
Billy called his sister that day: "He's gone Noreen. Doctor's say he went pretty quiet...but...he's gone. Dad's dead Noreen."
She sighed into the receiver, rolled her eyes back, and pushed a tear away:
"So what Billy....so what?"
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What's wrong about being the first sentient subquark haze?
Patents Drive Free Software as Hurricanes Drive Construction Industry
Two reasons:
* You need a bus, because even with quantum teleportation, you need to transmit (classical) information,
* You need a quantum bus, because you need entanglement for quantum communication, and that can only be transmitted through quantum channels (and quantum teleportation consumes entanglement).
Now since you have to transmit quantum states anyway, it would be silly to first transmit unrelated quantum states and then quantum-teleport the actual states using those, instead of just directly moving the real thing.
Note that the situation is different for large-distance transmission, where the errors in quantum transmission might be too high. In that case, it makes sense to send many particles carrying entanglement, which will partly decohere away, but you can distill perfectly entangled pairs from the remaining entanglement in order to transmit your actual quantum information through quantum teleportation using them (which only needs a robust classical channel). Note that even then you need a quantum channel for sending the entanglement, although it may be low-quality (you just have to transmit more entanglement then).
The Tao of math: The numbers you can count are not the real numbers.
As long as this computer is in an enclosed case it doesn't exist, happily, if you've got one of those cases with a plexi-glass side, it DOES exist.
[/war] "All the world's a stage, And all the men and women merely players."
...can it factor the number 16 yet?
I asked a few people about this, and none of them could explain:
If entanglement allows me to control whether another remote particle is in a "simple" position or a "super position", why is that not measurable?
The two-slit experiment, for example, is a measurement of whether the photons being shot are in a superposition of being in both slits, or if they are just in one of them.
So why can't the fact a particle is in a superposition or not be measured? A single result is not enough, ofcourse, but if you repeat the same measurement on multiple particles, you can see a bias, if they were in a superposition, can't you? Or, alternatively, if there is no way to measure the difference between a simple position or a superposition, in what sense do "super positions" exist at all?
Does this remind anyone else of the short fiction story I don't know, Timmy, Being God is a Big Responsibility?
Get a web developer
A superposition of states simply means that that the particle has an unknown value for the property being discussed. If you pick any random electron up off the street, its spin along any axis you choose to measure is in a superposition of states such that it might be up or down with equal probability. You can't measure this condition of being in a superposition of states because it is not a property of the electron. Rather, it is a condition of the information that you know about the electron. To use a bad coin flipping analogy, if you flip a coin and cover it before looking, you can say it is in a superposition of states between heads and tails with equal probability of each, not because there is anything special about the coin but because you simply don't know the definite answer.
Entanglement does not allow you to control anything at all about a distant particle. When particles are entangled, that means that measurements taken on both members of an entangled pair will correlate more often than our current understanding of the universe says should be possible. The measuring is a passive thing -- it gets information about the state of the particle. The correlations imply that somehow the entangled particles are linked over distance, or that the future of the pair of particles was predetermined at the time the entangled particles were created.
It cannot be exploited for communication because in order to even detect the strange correlations, you have to compare measurements, which requires getting information about those measurements to a common location. Suppose I'm doing an experiment with entangled photon polarization, and Alice is trying to send a message by modulating the angle of her polarizer. At Bob's detector, he's getting a 50% hit/miss with each photon that comes his way, no matter what angle Alice sets her polarizer to, and his measurement results are completely random.In order for Bob to decode the message, he has to know what Alice's measurements were. This is actually why photon entanglement is useful for encryption -- but it ain't gonna let us talk faster than light.
Fun with Anagarams! LADS HOST, SHALT DOS. HAS DOLTS. AD SLOTHS, HATS SOLD. ASS HO, LTD.
In the case of my workstation in a college lab, it's next to the radioactive waste.
...From immuno-assays. It was so low-level it barely registered on the Geiger counter. But it was in a 55gal drum.
True story
"Cheeze it!" - Bender
So you run 7 kits per kat? How do you deal with special karacters?
Rampant carbon sequestration destroyed the Dinosaurs' tropical paradise. I'm here to help repair the damage.
Using novel schemes, such as decoy states (very weak pulses that would let you spot any eavesdropper. Roughly), QKD has been demonstrated over 10km in commercial fibers.
... instantaneously. It can't be used to transfer information faster than the speed of light. This is different from not being able to transfer information.
snig
I believe I read in multiple sources about Quantum mechanics that a superposition is more than just a description of what we know about a particle.
The reason the 2 slit experiment has the result it has, is because each particle is in a superposition of being in both slits. If it passes through a single slit, but we don't know which, the cancellation pattern ceases. It must be in a superposition.
If this particle was entangled with some remote particle, and that remote particle had been measured, then the particle would have to choose a single slit to pass through, and would not create the pattern on the wall behind the slits.
That would work great for the government or other large organizations, but how could ordinary users protect, for instance, their online banking transactions once quantum computing becomes mainstream? How could you, for instance, access your banking information over routed networks (since QKD relies on a single unbroken fiber for photons to travel down in order to maintain coherance)
-Bucky