Skip to comments.Scientists Create Quantum Computer in a Diamond
Posted on 04/08/2012 11:20:22 AM PDT by Ernest_at_the_Beach
Scientists at the University of Southern California have created a computer within a diamond to test quantum computing theories. This research could lead to super computer speeds, but for the present is still in the experimental stage. A gratuitous tip of the hat to The Weazmeister for the linkage.
A qubit can represent a 0 and a 1 at the same time. This is thanks to the quantum property of superposition, and its the property that may one day make quantum computers insanely fast.
(Excerpt) Read more at enthusiast.hardocp.com ...
Don't believe they allow excerpts.
I can get a cubic zirconium computer for half price from a guy on the street.
As fast as a liberal calling someone a racist before they know the facts? No way, nothing is that fast.
How cool is this! When I get bored, I can just tune into the computer in my tux stud!
By Robert Perkins on April 5, 2012 7:30 AM
Diamonds are forever - or, at least, the effects of a diamond on quantum computing may be.
A team that includes scientists from USC has built a quantum computer in a diamond, the first of its kind to include protection against decoherence - noise that prevents the computer from functioning properly.
The demonstration showed the viability of solid-state quantum computers, which - unlike earlier gas- and liquid-state systems - may represent the future of quantum computing because they can easily be scaled up in size. Current quantum computers typically are very small and, though impressive, cannot yet compete with the speed of larger, traditional computers.
The multinational team included USC professor Daniel Lidar and USC postdoctoral researcher Zhihui Wang, as well as researchers from the Delft University of Technology in the Netherlands, Iowa State University and the University of California, Santa Barbara. The findings were published today in Nature.
The teams diamond quantum computer system featured two quantum bits, or qubits, made of subatomic particles.
As opposed to traditional computer bits, which can encode distinctly either a one or a zero, qubits can encode a one and a zero at the same time. This property, called superposition, along with the ability of quantum states to tunnel through energy barriers, some day will allow quantum computers to perform optimization calculations much faster than traditional computers.
Like all diamonds, the diamond used by the researchers has impurities - things other than carbon. The more impurities in a diamond, the less attractive it is as a piece of jewelry because it makes the crystal appear cloudy.
The team, however, utilized the impurities themselves.
A rogue nitrogen nucleus became the first qubit. In a second flaw sat an electron, which became the second qubit. (Though put more accurately, the spin of each of these subatomic particles was used as the qubit.)
Electrons are smaller than nuclei and perform computations much more quickly, but they also fall victim more quickly to decoherence. A qubit based on a nucleus, which is large, is much more stable but slower.
A nucleus has a long decoherence time - in the milliseconds. You can think of it as very sluggish, said Lidar, who holds appointments at the USC Viterbi School of Engineering and the USC Dornsife College of Letters, Arts and Sciences.
Though solid-state computing systems have existed before, this was the first to incorporate decoherence protection - using microwave pulses to continually switch the direction of the electron spin rotation.
Its a little like time travel, Lidar said, because switching the direction of rotation time-reverses the inconsistencies in motion as the qubits move back to their original position.
The team was able to demonstrate that its diamond-encased system does indeed operate in a quantum fashion by seeing how closely it matched Grovers algorithm.
The algorithm is not new - Lov Grover of Bell Labs invented it in 1996 - but it shows the promise of quantum computing.
The test is a search of an unsorted database, akin to being told to search for a name in a phone book when youve only been given the phone number.
Sometimes youd miraculously find it on the first try, other times you might have to search through the entire book to find it. If you did the search countless times, on average, youd find the name you were looking for after searching through half of the phone book.
Mathematically, this can be expressed by saying youd find the correct choice in X/2 tries - if X is the number of total choices you have to search through. So, with four choices total, youll find the correct one after two tries on average.
A quantum computer, using the properties of superposition, can find the correct choice much more quickly. The mathematics behind it are complicated, but in practical terms, a quantum computer searching through an unsorted list of four choices will find the correct choice on the first try, every time.
Though not perfect, Lidar and Wangs computer picked the correct choice on the first try about 95 percent of the time - enough to demonstrate that it operates in a quantum fashion.
The National Science Foundation and the U.S. Army Research Offices Multidisciplinary University Research Initiative funded the study.
I don’t understand how this could work. If a qubit can rep 1 or 0 at the same time how could that be processed? Is this similar to the John Kerry computer that he was against it while for it?
Very interesting, thanks for the post.
Now, diamonds are more than just a girl’s best friend. :)
I think that's great. Quantum Computing will open up the Software Engineering career field to a whole generation of students who can't grasp Boolean logic.
I smell BS.
It doesn't really matter whether the answer is 0 or 1 as long as the qubit feels good about it.
This is very interesting. I read that Michael Crichton book Timeline a few years back where he described how quantum computers work (or could work), and if I remember right, he said something like it operates in a multiverse or a parallel universe. That although the qubit is 1 and 0 at the same time, time does not exist on that level. Wooooosh........right over my head.
Made in China?
Grover's algorithm is a quantum algorithm for searching an unsorted database with N entries in O(N1/2) time and using O(logN) storage space (see big O notation). It was invented by Lov Grover in 1996.
Maybe they can explaine it.
Not sure that the link at post #21 helps.
That is a single atom with a nucleus and an electron could represent the following states ...with the electron as a 0 or a 1 depending on it;s spin and the same with the nucleus....thus the single "Proper Atom" could have four states or pairs....:
0 , 0
0 , 1
1 , 0
1 , 1
No Idea how you make that happen.
The left column would be the electron spin....the right column would be the nucleus spin.
Oops! Wrong diamond.
This is one of those fantastic claims that you will just have to take the experts’ word on.
So actually the atom could represent 0, `1, 2, or 3.... but not at the same time.
That statement must be from an illiterate (scientific ) technical journalist,,,,
ee #23 and #27.
It both helps and not-helps until you click on it.
That’s because of the theory behind quantum weirdness, though. It doesn’t actually have a “state” until it is measured. Until it is measured, it remains in an undefined state. So they say it can represent a 0 or a 1 at the same time.
Personally, though, I don’t elect to suspend disbelief. That is why I say that the scientists say it, but you’ll have to take their word for it. There is no way you can test or even fully understand their theory. Even they don’t understand it. If you question it, they will say that it doesn’t need to make sense, as long as it works experimentally. And you’ll also need to take their word for it when they say it works experimentally.
It's totally groovy!
Smile, Is, my other stud’s a camera!
This research could lead to super computer speeds, but for the present is still in the experimental stage... A qubit can represent a 0 and a 1 at the same time. This is thanks to the quantum property of superposition, and it's the property that may one day make quantum computers insanely fast.Good for nothing, but really fast.
How come measuring something changes it? How does an inanimate object know it’s being observed, to change spin or direction?
Isn’t that like saying a ruler has no length until I look at it, then it suddenly has length, or a rock has no weight until one looks at it...I don’t understand that principle.
The first one I understand. If you measure something, then you’ve got to touch it to do so, if only with a light beam. When you touch it, it moves (changes). But the idea that when you touch it, it sends an instantaneous message to another “entangled” object on the other side of the universe, and that object also changes, is difficult to accept. Yet, that is the theory. And the theory is generally accepted by most physicists. The “proof” is statistical.
Part of my skepticism is due to the fact that I don’t put much stock in statistics. The conclusions of statistical studies generally assume that you understand the mathematical structure of the phenomena you are studying. You’re just trying to measure the parameters. But in this case, you are actually trying to identify the mathematical structure of the phenomena you are studying.
I see what you mean. I wonder if the quantumness of “measuring things changes those things” would continue if there were a way to measure without ANY effect on the object being measured?
Entanglement seems so weird, two particles millions of parsecs away will each simultaneously move in like fashion when one moves??? Weird!
I wish I could understand how Einstein and others can figure out things from math...like, how did Einstein figure out the speed limit of light from math alone? It seems like me saying “2+2=4, therefore the speed of that pickup truck driving by is 70 mph.”
How can math alone figure out the precise speed of light? Wouldn’t they need some sort of measuring tool or something?
These are prolly the most basic, junior-high school physics facts, but...oh well!
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