Quantum computers could revolutionize the way we tackle problems that stump even the best classical computers.

Single atom transistor recently introduced has been seen as a tool that could lead the way to building a quantum computer. For general introduction how quantum computer work, read A tale of two qubits: how quantum computers work article.

D-Wave Announces Commercially Available Quantum Computer article tells that computing company D-Wave has announced that they’re selling a quantum computing system commercially, which they’re calling the D-Wave One. D-Wave system comes equipped with a 128-qubit processor that’s designed to perform discrete optimization operations. The processor uses quantum annealing to perform these operations.

D-Wave is advertisting a number of different applications for its quantum computing system, primarily in the field of artificial intelligence. According to the company, its system can handle virtually any AI application that can be translated to a Markov random field.

Learning to program the D-Wave One blog article tells that the processor in the D-Wave One – codenamed Rainier – is designed to perform a single mathematical operation called discrete optimization. It is a special purpose processor. When writing applications the D-Wave One is used only for the steps in your task that involve solving optimization problems. All the other parts of your code still run on your conventional systems of choice. Rainier solves optimization problems using quantum annealing (QA), which is a class of problem solving approaches that use quantum effects to help get better solutions, faster. Learning to program the D-Wave One is the first in a series of blog posts describing the algorithms we have run on D-Wave quantum computers, and how to use these to build interesting applications.

But is this the start of the quantum computers era? Maybe not. D-Wave Announces Commercially Available Quantum Computer article comments tell a story that this computer might not be the quantum computer you might be waiting for. It seem that the name “quantum computer” is a bit misleading for this product. There are serious controversies around the working and “quantumness” of the machine. D-Wave has been heavily criticized by some scientists in the quantum computing field. First sale for quantum computing article tells that uncertainty persists around how the impressive black monolith known as D-Wave One actually works. Computer scientists have long questioned whether D-Wave’s systems truly exploit quantum physics on their products.

Slashdot article D-Wave Announces Commercially Available Quantum Computer comments tell that this has the same central problem as before. D-Wave’s computers haven’t demonstrated that their commercial bits are entangled. There’s no way to really distinguish what they are doing from essentially classical simulated annealing. Recommended reading that is skeptical of D-Wave’s claims is much of what Scott Aaronson has wrote about them. See for example http://www.scottaaronson.com/blog/?p=639, http://www.scottaaronson.com/blog/?p=198 although interestingly after he visited D-Wave’s labs in person his views changed slightly and became slightly more sympathetic to them http://www.scottaaronson.com/blog/?p=954.

So it is hard to say if the “128 qubits” part is snake oil or for real. If the 128 “qubits” aren’t entangled at all, which means it is useless for any of the quantum algorithms that one generally thinks of. It seem that this device simply has 128 separate “qubits” that are queried individually, and is, essentially an augmented classical computer that gains a few minor advantages in some very specific algorithms (i.e. the quantum annealing algorithm) due to this qubit querying, but is otherwise indistinguishable from a really expensive classical computer for any other purpose. This has the same central problem as before: D-Wave’s computers haven’t demonstrated that their commercial bits are entangled.

Rather than constantly adding more qubits and issuing more hard-to-evaluate announcements, while leaving the scientific characterization of its devices in a state of limbo, why doesn’t D-Wave just focus all its efforts on demonstrating entanglement, or otherwise getting stronger evidence for a quantum role in the apparent speedup? There’s a reason why academic quantum computing groups focus on pushing down decoherence and demonstrating entanglement in 2, 3, or 4 qubits: because that way, at least you know that the qubits are qubits! Suppose D-Wave were marketing a classical, special-purpose, $10-million computer designed to perform simulated annealing, for 90-bit Ising spin glass problems with a certain fixed topology, somewhat better than an off-the-shelf computing cluster. Would there be even 5% of the public interest that there is now?

## 927 Comments

## Tomi Engdahl says:

Quantum Circuit Uses Just A Few Atoms

https://hackaday.com/2022/06/25/quantum-circuit-uses-just-a-few-atoms/

Researchers at the University of New South Wales and a startup company, Silicon Quantum Computing, published results of their quantum dot experiments. The circuits use up to 10 carbon-based quantum dots on a silicon substrate. Metal gates control the flow of electrons. The paper appears in Nature and you can download the full paper from there.

What’s new about this is that the dots are precisely arranged to simulate an organic compound, polyacetylene. This allowed researchers to model the actual molecule. Simulating molecules is important in the study of exotic matter phases, such as superconductivity. The interaction of particles inside, for example, a crystalline structure is difficult to simulate using conventional methods. By building a model using quantum techniques on the same scale and with the same topology as the molecule in question, simulation is simplified.

Engineering topological states in atom-based semiconductor quantum dots

https://www.nature.com/articles/s41586-022-04706-0

## Tomi Engdahl says:

Quantum computer cools itself down by performing calculations

As they warm up, quantum computers can slow down or stop working altogether. A new kind made with specially engineered diamonds cools as it calculates

https://www.newscientist.com/article/2326916-quantum-computer-cools-itself-down-by-performing-calculations/

## Tomi Engdahl says:

Quantum Computing for Dummies New guide helps beginners run quantum algorithms on IBM’s quantum computers over the cloud

https://spectrum.ieee.org/quantum-computing-for-dummies?share_id=7120649

## Tomi Engdahl says:

QUANTUM ERROR CORRECTION: TIME TO MAKE IT WORK

If technologists can’t perfect it, quantum computers will never be big

https://spectrum.ieee.org/quantum-error-correction?share_id=7101013

## Tomi Engdahl says:

Scientists Finally Create A Quantum Circuit At An Atomic Scale

An integrated circuit at this scale could pave the way for commercial quantum computers.

https://www.iflscience.com/scientists-finally-create-a-quantum-circuit-at-an-atomic-scale-64202

## Tomi Engdahl says:

D-Wave’s 500-Qubit Machine Hits the Cloud Experimental prototype offers sneak peek of 7,000-qubit quantum computer

https://spectrum.ieee.org/d-wave-quantum-computer?share_id=7129999

When quantum computing pioneer D-Wave releases its next-generation Advantage2 system in 2023 or 2024, the company expects their 7,000-qubit machine to be the most powerful quantum computer of its kind in the world. Now D-Wave is making an experimental prototype of Advantage2 immediately available for use over the cloud.

## Tomi Engdahl says:

Quantum Advantage Showdowns Have No Clear Winners

A series of recent experiments between quantum and classical computers shows the term’s ever-evolving meaning.

https://www.wired.com/story/quantum-advantage-showdowns-have-no-clear-winners/

## Tomi Engdahl says:

https://www.quantamagazine.org/quantum-algorithms-conquer-a-new-kind-of-problem-20220711/

## Tomi Engdahl says:

Researchers achieve record entanglement of quantum memories

https://phys.org/news/2022-07-entanglement-quantum-memories.html

## Tomi Engdahl says:

Record-setting quantum entanglement connects two atoms across 20 miles

https://newatlas.com/telecommunications/quantum-entanglement-atoms-distance-record/

## Tomi Engdahl says:

World’s first quantum computer integrated circuit

https://www.futuretimeline.net/blog/2022/07/3-worlds-first-quantum-computer-integrated-circuit.htm

The world’s first quantum computer integrated circuit has been demonstrated at the University of New South Wales (UNSW), Australia.

## Tomi Engdahl says:

Physicists Find The ‘Missing Link’ That Could Provide Quantum Internet Technology

https://www.sciencealert.com/physicists-find-the-missing-link-that-could-provide-quantum-internet-technology

Before quantum computers and quantum networks can fulfil their huge potential, scientists have got several difficult problems to overcome – but a new study outlines a potential solution to one of these problems.

## Tomi Engdahl says:

Researchers at Simon Fraser University have detected single spins optically in qubits in silicon for the first time, suggesting it may be possible to use light to “have qubits entangling with each other across a chip, or across a data center as easily as if they’re side-by-side.”

150,000 Qubits Printed on a Chip New silicon spin qubits also emit telecom-band light

https://spectrum.ieee.org/silicon-spin-qubits?utm_campaign=RebelMouse&socialux=facebook&share_id=7139305&utm_medium=social&utm_content=IEEE+Spectrum&utm_source=facebook

Quantum computers can theoretically solve problems no classical computer ever could even given billions of years, but only if they possess many components known as qubits. Now scientists have fabricated more than 150,000 silicon-based qubits on a chip that they may be able to link together with light, to help form powerful quantum computers connected by a quantum Internet.

## Tomi Engdahl says:

Poliittisesti tärkeä tehdas

Kiinan ja Yhdysvaltojen taistellessa kvanttitietokoneiden herruudesta, espoolaisen kerrostalon kellarissa humiseva konesali on Euroopan teknologiastrategian ytimessä. HS Visio vieraili 128 miljoonan euron jättirahoituksen keränneen teknologiayhtiön tehtaassa, jonne ulkopuolisilla ei tavallisesti ole mitään asiaa.

https://www.hs.fi/visio/art-2000008945213.html

## Tomi Engdahl says:

Scientists create quantum computer that breaks free of binary system

https://www.independent.co.uk/tech/quantum-computer-binary-qudit-science-b2128385.html#Echobox=1658416073

Scientists have made a quantum computer that breaks free from the binary system.

Computers as we know them today rely on binary information: they operate in ones and zeroes, storing more complex information in “bits” that either off or on. That seemingly simple system is at the heart of every computer we use.

Quantum computers have taken on that same system. They use qubits, which replicate the bits of a classical computer but using quantum technology.

But they are built with more than just those ones and zeroes. Quantum computers are not necessarily restricted to binary, and scientists hope that breaking them are from that system can add extra complexity without using more quantum particles.

Now scientists say they have succeeded in building a quantum computer that works in that way. It can do calculations not with qubits but instead with qudits – quantum digits that could allow for vastly more computing power.

## Tomi Engdahl says:

New Phase of Matter Opens Portal to Extra Time Dimension

Physicists have devised a mind-bending error-correction technique that could dramatically boost the performance of quantum computers

https://www.scientificamerican.com/article/new-phase-of-matter-opens-portal-to-extra-time-dimension/

## Tomi Engdahl says:

Team scripts breakthrough quantum algorithm

https://phys.org/news/2022-07-team-scripts-breakthrough-quantum-algorithm.html

City College of New York physicist Pouyan Ghaemi and his research team are claiming significant progress in using quantum computers to study and predict how the state of a large number of interacting quantum particles evolves over time. This was done by developing a quantum algorithm that they run on an IBM quantum computer. “To the best of our knowledge, such particular quantum algorithm which can simulate how interacting quantum particles evolve over time has not been implemented before,” said Ghaemi, associate professor in CCNY’s Division of Science.

## Tomi Engdahl says:

https://phys.org/news/2022-07-method-qubits-advance-quantum.html

## Tomi Engdahl says:

https://hackaday.com/2022/08/07/hackaday-links-august-7-2022/

If your personal edification shortlist includes understanding quantum programming, you could do worse than watching New Mind’s latest video on the subject. Where this one stands out for us is in the comparison of quantum concepts to what most of us already know about how digital computers work — how normal gates compare to quantum gates, for instance. We have to admit that the first watch-through didn’t entirely sink in — we’ll be giving it another go soon, hopefully before the next part is released.

Quantum Programming – Part 1

https://www.youtube.com/watch?v=2Eswqed8agg

## Tomi Engdahl says:

World’s Fastest 2-Qubit Gate: Breakthrough for the Realization of Ultrafast Quantum Computers

https://scitechdaily.com/worlds-fastest-2-qubit-gate-breakthrough-for-the-realization-of-ultrafast-quantum-computers/

## Tomi Engdahl says:

Traditional Computers Can Beat Google’s Quantum Computer Thanks To Smart Algorithm Design

The claim a quantum computer had finally achieved something traditional computers cannot has been challenged using superior algorithm design.

https://www.iflscience.com/traditional-computers-can-beat-googles-quantum-computer-thanks-to-smart-algorithm-design-64748

## Tomi Engdahl says:

https://phys.org/news/2022-07-alternative-superconducting-qubit-high-quantum.html#lightbox

## Tomi Engdahl says:

“Qudit” Computers Go Beyond Ones and Zeroes New machine works with eight qudits, each capable of encoding seven states at once

https://spectrum.ieee.org/qudit?share_id=7159724

## Tomi Engdahl says:

Simulating infinitely many chaotic particles using a quantum computer

https://phys.org/news/2022-08-simulating-infinitely-chaotic-particles-quantum.html

## Tomi Engdahl says:

Computer Science Proof Unveils Unexpected Form of Entanglement

Three computer scientists have posted a proof of the NLTS conjecture, showing that systems of entangled particles can remain difficult to analyze even away from extremes.

https://nautil.us/computer-science-proof-unveils-unexpected-form-of-entanglement-22240/

## Tomi Engdahl says:

Machine Learning Gets a Quantum Speedup

By

MAX G. LEVY

February 4, 2022

https://www.quantamagazine.org/ai-gets-a-quantum-computing-speedup-20220204/

Two teams have shown how quantum approaches can solve problems faster than classical computers, bringing physics and computer science closer together.