Intel Delivers 17-Qubit Superconducting Chip
newsroom.intel.com
newsroom.intel.com
https://techcrunch.com/2017/10/10/intel-moves-towards-produc...
What they're really proud of is essentially bringing Intel's manufacturing advantage to bear on an extremely new and different form of computing. Being able to iterate with new materials and architectures every few months is critical for testing, and it's there (as opposed to sheer numbers of qubits or whatever) that Intel hopes to outstrip the competition.
I was also surprised to learn that the cryo systems that get things down to a fraction of a kelvin are only the size of 50-gallon drums. I was picturing something much larger for anything that low. Now I know!
Wow. I could see something that size as per-workspace for specific use cases. Though what those use cases might be, I don't know. (Also, cost is probably the prohibitive factor right now...)
Still, I'd always imagined that quantum computers would start out as something that could only be done mainframe-like due to size. Perhaps not!
Contrast that to the cooling D-Wave uses. It's not all cooling but it gives you an idea of the cooling apparatus: https://youtu.be/zDotDiK2UuY?t=50
Is it essentially just heat-removal + lots of layers of isolated, effective insulation, or are there fundamental differences when you're going that low?
I won't even try to summarise it - I'm sure I'd get it wrong! Fascinating stuff though.
The way cooking it was explained to me is that you try to slow down atoms with lasers, but I don’t know any of the details.
Claude Cohen danucci received a nobel and a wolf for this (and other things)
They mention surface codes which are related to toric codes and toric codes are a part of topological quantum computation [1]. A explanation of toric codes can be found at [3]
Their website says that they specialize in Topological Quantum Computers and Quantum Error correction (which are a feature of Topological Quantum Computers. Also the link to the researchers website mentions similar projects . [2]
[0] https://en.wikipedia.org/wiki/Topological_quantum_computer
[1] https://arxiv.org/pdf/0904.4165v2.pdf
[2] https://qutech.nl/roadmaps/ http://dicarlolab.tudelft.nl
[3] https://physics.stackexchange.com/questions/29310/what-is-co...
[1]: https://www.bloomberg.com/news/articles/2017-09-13/ibm-makes...
D-Wave [1] is shipping quantum computers with thousands of qubits. The difference seems to be that D-Wave qubits are not generalized qubits, but rather they are simply designed to solve problems using quantum annealing [1]. Annealing is just one algorithm which efficiently (but probabilistically) looks for the global minimum of a function, but it is prone to getting stuck in local minima. Quantum annealing exploits quantum phenomena to do this better and probably more efficiently [2].
On the other hand, we have "general" qubits: these can implement and carry out any arbitrary quantum computing algorithm (for example, Grover's search algorithm or Shor's factorization algorithm). It seems to me that researchers at Alphabet, Rigetti, Intel, IBM, etc. are trying to build these general qubits, since that's where we can finally unlock the full power of quantum computing. It's also much harder to build these general qubits, and that's why we only see 17 qubits announced here, or Google claiming to be working on 49 qubits [3].
[1] https://www.dwavesys.com/sites/default/files/D-Wave%202000Q%...
[2] https://en.wikipedia.org/wiki/Quantum_annealing
[3] https://www.bloomberg.com/news/articles/2017-07-17/google-s-...
I heard someone say that once we got to 50 qubits, we would be able to unlock the potential of quantum computers/actually solve problems that are nontrivial for traditional computers. If that's the case, why is google stopping just before that threshold?
Of course, it could be marketing running away with it.
Like, how does one produce logic gates out of them? How do you create an IEEE 754 Floating point multiplier? I get that they're supposed to represent overlaid states on the same device due to Pauli exclusion, but how do you separate out states and use them in logic? Or save states? What happens if logic produces the same state for one device? Is standard metal used to send signals, or is it something fancy-dancy like neutrinos?
It's honestly the most exotic thing I know of in tech, just trying to even begin to get a handle on it, never-mind trying to perform useful work out of them.
For me myself one of the easiest concepts to understand was quantum annealing (https://en.wikipedia.org/wiki/Quantum_annealing). It does not mean that's the strongest point of quantum computers, but it's a nice way to start.
By the way - you could as well simulate a quantum computer on a classical computer; it'd just be incredibly slow.
It describes the kinds of computations that need reversible computations and kinds of devices that can perform them. That makes it easier to notice similarities, as quantum computers are not the only ones in this category. Notably, photonic and low power computations call for reversibility.
The first couple of pages of the paper also touch upon what can be done with them - while you don't have to throw away all you knew about logic gates, the reversible ones are their own thing.
If the water goes too deep, perhaps Mika Hirvensalo's "Quantum computing" helps. It approaches the topics of how to compute with qubits from mathematical side.
I still don't know the theory behind quantum annealing though - I don't think these two cover it.
Still, I learned that the main difference is that the state doesn't have to travel as with electronic circuits, but rather one would likely "apply" gates as "events" acting on the state. A qubit could then be any quantum object - a electron trapped in one place and being hit with photons for example. Place a couple together and hit them in a coordinated way and that event was your gate.
When it comes to saving states, it will be problematic. Of course, it's possible to "save" a qubit to another qubit - with some workarounds for the "no-cloning" principle.
But if you mean saving them to a classical system, it seems it's not possible at all. A qubit is a representation of a probability, and once read it's destroyed. You could try recalculating it several times and get an idea of the probability it represents. However, qubit readouts are not guaranteed to be independent from one another, giving another bit of headache here.
Disclaimer: I'm not a physicist - just a software engineer trying to understand the hype.
* https://www.youtube.com/watch?v=F8U1d2Hqark * https://www.youtube.com/watch?v=ZoT82NDpcvQ
https://phys.org/news/2017-10-quantum-computingbreaking-qubi...
Best contenders I see so far are supersingular isogeny ECC and NTRU or other lattice based algorithms.
So either:
- I'm wrong, and some phenomenon exists that can differentiate the theories.
- The only thing about quantum computing that will change if the Copenhagen interpretation falls out of favor is the contents of the textbooks
The De Broglie-Bohm interpretation doesn't have this problem, because it does not distinguish between quantum interactions and "measurements"; they are one and the same.
It is correct to say that all interpretations lead to the same predictions, but not actually correct to say they're the same mathematical model.
Edit: I was incorrect. Today I learned that Copper Pairs are being used as the qubits.
No. Superposition (in a qubit sense) is not necessary for superconductivity. Most quantum computer designs require superconductivity, but it is not a strict requirement. Photon based quantum computers don't need any superconductivity iirc.
> it is a superconducting chip, and that is a major engineering problem
Superconductivity is not a super high bar. The bigger issue from quantum computing is coherence time; and it just happens that low temperatures are critical for lengthening it.
edit: also, I meant superconducting was (practically) required for superposition, but not vice-versa. I guess I misused the phrase one-required-for-the-other.
I believe that everywhere superconducting was used it was correct and using superposition instead would be wrong. So I agree with you there.
I am not sure what you mean here. Superconducting magnets are often used to control plasma (part of the environment) so it doesn't imply isolation from the environment.
Superconducting qubits are only superconducting because josephson junctions happen to be good candidates to make qubits out of. Ion traps (which generally have much better coherence times than superconducting qubits) and photon based systems don't need superconductivity.
I'm not sure how to make it more clear, but decoherence happens because some energy / information is transmitted into the environment. That loss of information is why superpositions collapse.
Maybe the confusion is what I mean by superconducting - I mean zero resistance circuits. It's not about what it's made of.
To wit, can they afford not to sink money into it, if their competitors are, even if success if less than certain?
The rewards that seem like they would be realized are generational enough so as to render much of the existing market obsolete. So to be caught without any expertise, on a risk-basis is more costly than seemingly dumping money down the drain.
If you measure the qubit prematurely the function collapses. In classical computing it might be analogous to breaking out of a for loop before it has run its intended course and then you're left with an incorrect (or incomplete) answer.
If n is 20, you're not really beating a 6502.
Being quantum lets a chip scale its speed better. But that's about it. At this size, it's worse in every single way than a normal processor.
Congrats Intel!