Quantum Motion unveils 9-second silicon qubit
Quantum Motion, a four-year-old UK-based startup is today announcing a quantum computing breakthrough, demonstrating that a stable qubit can be created on a standard silicon chip, similar to those used in smartphones.
[...] Even chipmaker Intel, which is testing a similar silicon-based approach in collaboration with Delft-based startup QuTech, talks about times of 1 second — and this is several orders of magnitude longer than what has been achieved by quantum companies using the superconducting approach.
[...] But more importantly, if the silicon approach works, the quantum computer industry would not have to build a new set of chip foundries — they could use the infrastructure that is already there. It would also be easier to combine quantum and classic computers if both use the same silicon chip and transistor architecture.
[...] Some of the quantum computing technologies may also be quite bulky when you scale up to multiple thousands of qubits. But in theory, a million of Quantum Motion's electron-spin qubits could be packed onto a 1cm square chip. You would still need the elaborate chandelier-like refrigerator to keep the chips at a fraction of a kelvin above absolute zero, but just one such refrigerator — similar in size to a server rack — can hold many chips.
Also at TechRadar.
Journal Reference:
Virginia N. Ciriano-Tejel, Michael A. Fogarty, Simon Schaal, et al. Spin Readout of a CMOS Quantum Dot by Gate Reflectometry and Spin-Dependent Tunneling [open], PRX Quantum (DOI: 10.1103/PRXQuantum.2.010353)
(Score: 2) by maxwell demon on Saturday April 03 2021, @07:25AM (7 children)
From the article:
I have to disagree. The step from one qubit to two qubits is huge. That's because for a single qubit, all that matters is how well you shield it from any outside influence causing decoherence (and yes, a decoherence time of nine seconds is massively impressive!). But for a two-qubit system, you additionally have to control the coupling between the two qubits in a way that doesn't break the coherence. That is, you have to have an interaction between the qubits that you can switch on and off at will, in a way that doesn't break coherence. Note that this is different from readout, which is a process that necessarily breaks coherence.
The Tao of math: The numbers you can count are not the real numbers.
(Score: 2) by Mojibake Tengu on Saturday April 03 2021, @08:37AM (1 child)
You mean, like these?
https://rosatomnewsletter.com/2020/02/25/quantum-breakthrough/ [rosatomnewsletter.com]
See the roadmap.
Respect Authorities. Know your social status. Woke responsibly.
(Score: 2, Disagree) by maxwell demon on Sunday April 04 2021, @07:44AM
I don't see the relevance of your link. It has about zero relation to what I wrote.
The Tao of math: The numbers you can count are not the real numbers.
(Score: 0) by Anonymous Coward on Saturday April 03 2021, @01:48PM (3 children)
What is the difference between a quantum computer and an analog computer?
(Score: 2) by maxwell demon on Sunday April 04 2021, @07:46AM (2 children)
Classical analogue computers don't have entanglement.
The difference between a quantum digital computer and a quantum analogue computer is of course roughly the same as the difference between a classical digital and a classical analogue computer.
The Tao of math: The numbers you can count are not the real numbers.
(Score: 0) by Anonymous Coward on Sunday April 04 2021, @12:09PM (1 child)
Isn't the only role of entanglement to allow correlated bits, which you can do with an analogue computer.
(Score: 0) by Anonymous Coward on Sunday April 04 2021, @05:18PM
Analog computers don't have bits. They use state variables
(like a voltage level) that have a continuous range of values, and use them in analog circuits that carry out the operations.
(Score: 0, Informative) by Anonymous Coward on Saturday April 03 2021, @10:00PM
Precisely controlled coupling is necessary, but switching is not,
You could build a quantum computer pre-wired for a specific problem.
The time to design, fab, and run might still be shorter than on normal logic.
I'm waiting to see a machine that can factor 15=3*5, then one that can do 35=5*7, then 77= 7*11, etc.
(Score: 0) by Anonymous Coward on Saturday April 03 2021, @07:40AM (1 child)
Here I'm beginning to master programming a Lovelace-Turing machine, and so instead they invent something even weirder that needs programming.
(Score: 0) by Anonymous Coward on Sunday April 04 2021, @07:53AM
Don't worry, by the time it gets to you it will be a single Problem.solve() call that you can congratulate yourself for copy/pasting from stackoverflow.
(Score: 0) by Anonymous Coward on Saturday April 03 2021, @11:32AM (2 children)
So still not usable for quantum porn.
(Score: 0) by Anonymous Coward on Sunday April 04 2021, @07:48AM (1 child)
I can see the follow up joke... I... I CAN SEE EVERYTHING OH MY GOD
(Score: 0) by Anonymous Coward on Sunday April 04 2021, @07:54AM
This must be an alternative universe where jokes are not funny?