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?
1,130 Comments
Tomi Engdahl says:
On-chip frequency shifters in the gigahertz range could be used in next generation quantum computers and networks
https://phys.org/news/2021-11-on-chip-frequency-shifters-gigahertz-range.html
Tomi Engdahl says:
https://www.cnet.com/tech/computing/us-blocks-export-of-quantum-computing-tech-to-chinese-organizations/
Tomi Engdahl says:
https://scitechdaily.com/a-nanoantenna-for-long-distance-ultra-secure-quantum-communication/
Tomi Engdahl says:
Math may have caught up with Google’s quantum-supremacy claims
But, given the rapidly evolving quantum computing landscape, that may not matter.
https://arstechnica.com/science/2021/11/math-may-have-caught-up-with-googles-quantum-supremacy-claims/
Tomi Engdahl says:
https://scitechdaily.com/exotic-new-material-could-be-two-superconductors-in-one-with-serious-quantum-computing-applications/
Tomi Engdahl says:
Physicists achieve fault-tolerant control of an error-corrected qubit
https://physicsworld.com/physicists-achieve-fault-tolerant-control-of-an-error-corrected-qubit/
Tomi Engdahl says:
IBM’s Eagle, a 127 Qubit Quantum Processor
https://blog.adafruit.com/2021/11/28/ibms-eagle-a-127-qubit-quantum-processor/
via Engadget
IBM claims it has taken a major step toward practical quantum computation. On Monday, the company unveiled Eagle, a 127 qubit quantum processor. IBM claims it’s the first such processor that can’t be simulated by a classical supercomputer. To make sense of what that means, the company says to simulate Eagle you would need more classical bits than there are atoms in every human being on the planet. IBM is crediting the breakthrough to a new design that puts the processor’s control components on multiple physical levels while the qubits are located on a single layer. It’s a design the company says allows for a significant increase in computing power.
https://www.engadget.com/ibm-eagle-processor-050133991.html
Tomi Engdahl says:
White House Blacklists 8 Chinese Quantum Computing Companies Citing National Security Risks: Report
https://dailyhodl.com/2021/11/28/white-house-blacklists-8-chinese-quantum-computing-companies-citing-national-security-risks-report/
The Biden Administration has announced that it is blacklisting eight Chinese quantum computing companies over concerns that the technology they possess poses a threat to national security.
The companies have been added to the U.S. Department of Commerce’s Entity List, which is a national security tool used by the Bureau of Industry and Security (BIS).
Tomi Engdahl says:
https://www.uusiteknologia.fi/2021/11/30/suomen-ensimmainen-viiden-kubitin-kvanttitietokone-on-valmis/
Tomi Engdahl says:
Näin toimii juuri valmistunut kvanttitietokone – Suomi teki ensimmäisten joukossa koneen, jonka monituhatkertainen laskentanopeus mullistaa lukuisat alat
https://yle.fi/uutiset/3-12209593
Oma kvanttitietokone on suuri lupaus Suomen kvanttialalle, jossa tehdään jo ehtaa bisnestä. Koneiden tulevat loppukäyttäjät eli muu yrityskenttä voi saada tuntuvan kilpailuedun, jos valmistautuminen aloitetaan ajoissa.
Kvanttitietokoneet saadaan tosikäyttöön jo pian
Missä huippunopeasta laskennasta sitten on hyötyä?
Esimerkiksi lääkeaineiden ja kemianteollisuuden yhdisteiden kehitys nopeutuisi erittäin paljon, logistiikan optimointi vähentäisi valtavasti turhia kilometrejä, energian tuotanto ja jakelu tehostuisi. Ilmastonmuutoksen ja meteorologian tutkimus harppaisi jättiaskeleen, tietoturva paranisi valtavasti ja rahoituslaskelmat vähentäisivät potentiaalisesti riskejä finanssialalla.
Toistaiseksi käytännön sovellutuksia saadaan odottaa.
– Todellista hyötyä kvanttitietokoneista aletaan kuitenkin saada jo hyvin pian, alan yleisen arvion mukaan vuosina 2025–26, VTT:n Himadri Majumdar sanoo.
Nykyiset kvanttitietokoneet ovat vasta eräänlaisia prototyyppejä kehityksessä kohti loppukäyttäjille hyödyllistä konetta. Sama pätee Suomessa valmistettuun kvanttitietokoneeseen.
Oleellista on, että niillä on kuitenkin jo kyetty ratkomaan huippunopeita laskutoimituksia.
– Kuuluisin tapaus on vuodelta 2019, jolloin Google ilmoitti laskeneensa kvanttitietokoneella 200 sekunnissa ongelman, johon olisi mennyt supertietokoneella viikkoja, kuukausia tai jopa vuosia, VTT:n Pekka Pursula sanoo.
Majumdar toteaa, että 2030-luvulla kvanttilaskennan hyödyt alkavat näkyä jo laajasti yhteiskunnassa ja ihmisten arjessa. Vielä pidemmälle mentäessä edessä on sovellutuksia, joista ei nyt osata uneksiakaan.
Suomessa kvanttiteknologiat ovat jo ehtaa bisnestä
Suomalainen kvanttitietokone vie VTT:n Himadri Majumdarin ja Pekka Pursulan mukaan kotimaista kvanttiteknologian tutkimusta, opetusta ja alan yrityksiä voimakkaasti eteenpäin.
Ala kasvaa kansainvälisesti useita kymmeniä prosentteja vuodessa, joten bisnesmahdollisuuksia riittää.
Kvanttiteknologioiden parissa työskentelee jo Suomessa suunnilleen 15 firmaa, joiden yhteenlaskettu liikevaihto lähentelee sataa miljoonaa euroa. Lisäksi on kasvava määrä startup-yrityksiä ja yliopistoilla syntyy uutta yritystoimintaa.
Nopeasti kasvavia yhtiöitä ovat esimerkiksi jäähdyttimiä valmistava Bluefors sekä kvanttitietokoneen rakentanut IQM
Majumdarin sanoo, että Suomessa on vahvaa osaamista sekä kvanttiteknologioiden komponenttivalmistuksessa että ohjelmistokehityksessä.
– Uusia firmoja syntyy todennäköisesti etenkin ohjelmistopuolelle, jossa kehitetään esimerkiksi algoritmejä kvanttilaskentaan.
Kilpailu alalla on todella kovaa ja suurvallat laittavat tällä hetkellä miljardeja kvanttitietokoneiden kehittämiseen. Suomen valtio rahoitti kvanttitietokoneen rakentamista runsaalla 20 miljoonalla eurolla.
Tomi Engdahl says:
Physicists Confirm The Existence of Time Crystals in Epic Quantum Computer Simulation
https://www.sciencealert.com/physicists-used-a-quantum-computer-to-show-their-time-crystal-design-is-the-real-deal
Are you in the market for a loophole in the laws that forbid perpetual motion? Knowing you’ve got yourself an authentic time crystal takes more than a keen eye for high-quality gems.
Tomi Engdahl says:
Stanford’s Simple New Quantum Computer Design: Photonic Computation in a Synthetic Time Dimension
https://scitechdaily.com/stanfords-simple-new-quantum-computer-design-photonic-computation-in-a-synthetic-time-dimension/
A relatively simple quantum computer design that uses a single atom to manipulate photons could be constructed with currently available components.
Now, Stanford University researchers have proposed a simpler design for photonic quantum computers using readily available components, according to a paper published on November 29, 2021, in Optica. Their proposed design uses a laser to manipulate a single atom that, in turn, can modify the state of the photons via a phenomenon called “quantum teleportation.” The atom can be reset and reused for many quantum gates, eliminating the need to build multiple distinct physical gates, vastly reducing the complexity of building a quantum computer.
Tomi Engdahl says:
Stanford’s Simple New Quantum Computer Design: Photonic Computation in a Synthetic Time Dimension
https://scitechdaily.com/stanfords-simple-new-quantum-computer-design-photonic-computation-in-a-synthetic-time-dimension/
Tomi Engdahl says:
AWS Braket gets improved support for hybrid quantum-classical workloads
https://techcrunch.com/2021/11/29/aws-braket-gets-improved-support-for-hybrid-quantum-classical-workloads/
In 2019, AWS launched Braket, its quantum computing service that makes hardware and software tools from its partners Rigetti, IonQ and D-Wave available in its cloud. Given how quickly quantum computing is moving ahead, it’s maybe no surprise that a lot has changed since then. Among other things, hybrid algorithms that use classical computers to optimize quantum algorithms — a process similar to training machine learning models — have become a standard tool for developers. Today, AWS announced improved support for running these hybrid algorithms on Braket.
Previously, to run these algorithms, developers would have to set up and manage the infrastructure to run the optimization algorithms on classical machines and then manage the integration with the quantum computing hardware, in addition to the monitoring and visualization tools for analyzing the results.
Tomi Engdahl says:
How Much Has Quantum Computing Actually Advanced? Q&A with the former chief architect of Google’s Sycamore, John Martinis
https://spectrum.ieee.org/quantum-computing-google-sycamore?share_id=6810989
Lately, it seems as though the path to quantum computing has more milestones than there are miles. Judging by headlines, each week holds another big announcement—an advance in qubit size, or another record-breaking investment: First IBM announced a 127-qubit chip. Then QuEra announced a 256-qubit neutral atom quantum computer. There’s now a new behemoth quantum computing company, “Quantinuum” thanks to the merger of Honeywell Quantum Solutions and Cambridge Quantum. And today, Google’s Sycamore announced another leap toward quantum error correction.
A curmudgeon might argue that quantum computing is like fusion, or any promising tech whose real rewards are—if even achievable—decades off. The future remains distant, and all the present has for us is smoke, mirrors, and hype.
Tomi Engdahl says:
Researchers propose a simpler design for quantum computers
https://phys.org/news/2021-11-simpler-quantum.html
Tomi Engdahl says:
Quantum science and technology is a hot ticket today, with governments, major tech companies and financiers around the world pouring money into research and development. As a result, the need to understand the basics of things like quantum computing and quantum cryptography goes well beyond the academic community. The problem, however, is that the concepts underlying these technologies can be fiendish to understand – even for physicists working in fields other than quantum information.
What you need to know before investing in quantum technology
https://physicsworld.com/a/what-you-need-to-know-before-investing-in-quantum-technology/
Quantum science and technology is a hot ticket today, with governments, major tech companies and financiers around the world pouring money into research and development. As a result, the need to understand the basics of things like quantum computing and quantum cryptography goes well beyond the academic community. The problem, however, is that the concepts underlying these technologies can be fiendish to understand – even for physicists working in fields other than quantum information.
As a result, there is a growing need for guides to the quantum technology aimed at the layperson who might be interested in investing in a quantum technology company or a businessperson who might want to use the products or services of such a company.
Tomi Engdahl says:
Thomas Black / Bloomberg:
Quantinuum, recently spun off from Honeywell, offers the first product created solely by a quantum computer, encryption keys that it claims can’t be predicted
https://www.bloomberg.com/news/articles/2021-12-07/honeywell-unit-offers-first-ever-quantum-created-encryption-key
Tomi Engdahl says:
Suomalaistutkijat rakensivat mikroaaltolähteen kubittien ohjaamiseen
https://etn.fi/index.php/13-news/12936-suomalaistutkijat-rakensivat-mikroaaltolaehteen-kubittien-ohjaamiseen
Suomalaiset kvanttifyysikot ovat onnistuneet rakentamaan kubittien ohjaukseen soveltuvan mikroaaltolähteen, joka toimii erittäin matalissa lämpötiloissa. Sen teho on sata kertaa aiempaa suurempi ja siksi riittävä kubittien hallintaan. Lisäksi mikroaaltolähteestä aiheutuvat virheet kvanttilaskentaan ovat vähäisiä.
Isoja kvanttiprosessoreita hallitaan ajamalla mikroaaltosignaalien sarja kubitteihin eli kvanttibitteihin. Kubitin ohjaukseen käytettävä nopea mikroaaltosignaali kulkee kaapelia pitkin kryostaattiin eli superpakastimeen, jossa kvanttiprosessori sijaitsee.
Nyt rakenteilla olevissa kvanttitietokoneissa on vain rajallisesti kubitteja. Kun kubittien määrä tulevaisuudessa kasvaa yli kymmeniin tuhansiin, loppuu tila jättimäisissäkin kryostaateissa, mikäli jokaista kubittia varten tarvitaan oma kaapelinsa. Vastaan tulee myös lämpöongelma: kryostaatti ei jaksa jäähdyttää kaapeleita.
Tomi Engdahl says:
A low-noise on-chip coherent microwave source
https://www.nature.com/articles/s41928-021-00680-z
The scaling up of quantum computers operating in the microwave domain requires advanced control electronics, and the use of integrated components that operate at the temperature of the quantum devices is potentially beneficial. However, such an approach requires ultralow power dissipation and high signal quality to ensure quantum-coherent operations. Here we report an on-chip device that is based on a Josephson junction coupled to a spiral resonator and is capable of coherent continuous-wave microwave emission. We show that the characteristics of the device accurately follow a theory based on the perturbative treatment of a capacitively shunted Josephson junction as the gain element. The infidelity of typical quantum gate operations due to phase noise of this cryogenic 25 pW microwave source is less than 0.1% up to 10 ms evolution time, which is below the infidelity caused by dephasing in state-of-the-art superconducting qubits. Together with future cryogenic amplitude and phase modulation techniques, our approach may lead to scalable cryogenic control systems for quantum processors.
Tomi Engdahl says:
Uusi mikroaaltokeksintö voi lisätä kvanttitietokoneiden tehokkuutta
https://www.uusiteknologia.fi/2021/12/10/uusi-mikroaaltokeksinto-voi-lisata-kvanttitietokoneiden-tehokkuutta/
Aalto-yliopiston ja VTT:n kvanttifyysikot onnistuivat rakentamaan tulevaisuuden kvanttitietokoiden kubittien ohjaukseen soveltuvan uudenlaisen mikroaaltolähteen, joka toimii erittäin matalissa lämpötiloissa. Sen teho on sata kertaa aiempaa suurempi.
Tomi Engdahl says:
John Timmer / Ars Technica:
Researchers find that cosmic rays and radioactivity interfere with error correction in quantum computing
A potential hangup for quantum computing: Cosmic rays
For quantum chips, the problems they cause are too big for error correction.
https://arstechnica.com/science/2021/12/cosmic-rays-can-swamp-error-correction-on-quantum-processors/
Recently, when researchers were testing error correction on Google’s quantum processor, they noted an odd phenomenon where the whole error-correction scheme would sporadically fail badly. They chalked this up to background radiation, a combination of cosmic rays and the occasional decay of a naturally occurring radioactive isotope.
It seemed like a bit of an amusing aside at the time—Google having accidentally paid for an extremely expensive cosmic ray detector. But the people behind the processor took the problem very seriously and are back with a new paper that details exactly how the radiation affects the qubits. And they conclude that the problems caused by cosmic rays happen often enough to keep error-corrected quantum computations from working unless we figure out a way to limit the rays’ impact.
It’s a shame about the rays
Cosmic rays and radioactivity cause problems for classical computing hardware as well. That’s because classical computers rely on moving and storing charges, and cosmic rays can induce charges when they impact a material. Qubits, in contrast, store information in the form of the quantum state of an object—in the case of Google’s processor, a loop of superconducting wire linked to a resonator. Cosmic rays affect these, too, but the mechanism is completely different.
Tomi Engdahl says:
China’s New Quantum Computer Has 1 Million Times the Power of Google’s
https://www.scientiststudy.com/2021/10/chinas-new-quantum-computer-has-1.html?m=1
In July this year, a team in China demonstrated that it has the world’s most powerful quantum computer, finally leapfrogging Google, who claimed to have achieved quantum supremacy back in 2019. Back then, China was touting a super-advanced 66-qubit quantum supercomputer called “Zuchongzhi” as a contender against Google’s 54-qubit Sycamore processor. But while Google’s quantum computers have not progressed noticeably since then, China on the other hand never slowed down, coming up with more powerful quantum processors.
According to a recent study published in peer-reviewed journal Physical Review Letters and Science Bulletin, physicists in China claim they’ve constructed two quantum computers with performance speeds that far outrival competitors in the US or indeed anywhere in the world — debuting a superconducting machine along with a speedier unit that uses light photons to obtain unprecedented results.
What makes the latest revelation more interesting is the fact that the light-based Jiuzhang 2 can calculate in one millisecond, a task that would take the world’s fastest conventional computer up to 30 trillion years. It basically has a narrower field of applications but can reach a speed of 100 sextillion (one followed by 23 zeros) times faster than the largest conventional computers.
Jiuzhang 2 is actually an upgrade of a machine built by Pan’s team last year, uses photons, each one carrying a qubit – the basic unit of quantum information. Lead scientist with the Jiuzhang project, Lu Chaoyang highlighted that they “have increased the number of photons from 76 to 113, (the new machine) is billions of billions of times faster than supercomputers.”
Tomi Engdahl says:
Here’s What a World Powered by Quantum Computers Will Look Like
https://www.thespaceacademy.org/2021/12/heres-what-world-powered-by-quantum.html?m=1
Tomi Engdahl says:
Aalto-tutkijat ottivat ison askeleen kohti virheettömästi toimivia kvanttikoneita
https://etn.fi/index.php/13-news/12990-aalto-tutkijat-ottivat-ison-askeleen-kohti-virheettoemaesti-toimivia-kvanttikoneita
Kvanttitietokoneiden kubittien piirit tehdään suprajohtavista materiaaleista, joissa ei ole lainkaan sähkövastusta. Suprajohtavuus ja siten kubittien suorituskyky heikkenee, jos suprajohteissa on pariutuneiden elektronien eli Cooperin parien lisäksi pariutumattomia elektroneja eli kvasihiukkasia. Aalto-yliopiston tutkijat ovat nyt onnistuneet tarkkailemaan kvasihiukkasten poistumista.
Kvasihiukkaset eli parittomat elektronit pysyivät poissa sekunteja, mikä on enemmän kuin tarpeeksi suprajohtavan kvanttibitin operaatioihin. Tulos on merkittävä askel kohti virheettömästi toimivia kvanttitietokoneita.
- Vaikka kvasihiukkasia olisi vain yksi miljardia Cooperin paria kohden, se rajoittaa kvanttibittien suorituskykyä eikä kvanttitietokone voi toimia virheettömästi. Jos pariutumattomia hiukkasia on enemmän, myös kubitin elinikä on lyhyempi, sanoo Aallossa kvasipartikkeleita tutkinut Elsa Mannila, joka nykyisin työskentelee VTT:llä.
Aalto-yliopiston tutkijat havainnoivat yhdessä Lundin yliopiston ja VTT:n tutkijoiden kanssa reaaliaikaisesti pienellä alumiinisaarekkeella olevien kvasihiukkasten määrää. Tutkijat pystyivät varausilmaisimen avulla tarkkailemaan, miten Cooperin parien hajoamisesta syntyvät parittomat elektronit tunneloituivat eli karkasivat yksi kerrallaan pois alumiinisaarekkeelta noin sadan mikrosekunnin kuluessa.
Alumiinisaareke oli kokeessa sekunteja ilman ylimääräisiä elektroneja – paljon pidempään kuin mitä suprajohtavilta kvanttibiteiltä kuluu operaatioiden suorittamiseen.
- Kvasihiukkasista halutaan aina eroon. Tutkimus on siten olennainen askel ideaalisesti toimivien suprajohtavien laitteiden rakentamisessa”, kertoo professori Jukka Pekola.
Tomi Engdahl says:
Uusia keino virheettömään kvanttilaskentaan
https://www.uusiteknologia.fi/2021/12/21/uusia-keino-virheettomaan-kvanttilaskentaan/
Aalto-yliopiston tutkijat ovat todistaneet kokeissaan kvanttitietokonetta häiritsevien kvasihiukkasten katoamisen. Parittomat elektronit pysyivät kokeissa poissa sekunteja, mikä on enemmän kuin tarpeeksi suprajohtavan kvanttibitin operaatioiden tekemiseen. Tulos onkin merkittävä askel kohti tulevaisuuden virheettömästi toimivia kvanttitietokoneita.
Aalto-tutkijat ottivat ison askeleen kohti virheettömästi toimivia kvanttikoneita
https://etn.fi/index.php/13-news/12990-aalto-tutkijat-ottivat-ison-askeleen-kohti-virheettoemaesti-toimivia-kvanttikoneita
Kvanttitietokoneiden kubittien piirit tehdään suprajohtavista materiaaleista, joissa ei ole lainkaan sähkövastusta. Suprajohtavuus ja siten kubittien suorituskyky heikkenee, jos suprajohteissa on pariutuneiden elektronien eli Cooperin parien lisäksi pariutumattomia elektroneja eli kvasihiukkasia. Aalto-yliopiston tutkijat ovat nyt onnistuneet tarkkailemaan kvasihiukkasten poistumista.
Kvasihiukkaset eli parittomat elektronit pysyivät poissa sekunteja, mikä on enemmän kuin tarpeeksi suprajohtavan kvanttibitin operaatioihin. Tulos on merkittävä askel kohti virheettömästi toimivia kvanttitietokoneita.
- Vaikka kvasihiukkasia olisi vain yksi miljardia Cooperin paria kohden, se rajoittaa kvanttibittien suorituskykyä eikä kvanttitietokone voi toimia virheettömästi. Jos pariutumattomia hiukkasia on enemmän, myös kubitin elinikä on lyhyempi, sanoo Aallossa kvasipartikkeleita tutkinut Elsa Mannila, joka nykyisin työskentelee VTT:llä.
Tomi Engdahl says:
https://scitechdaily.com/new-performance-benchmark-measuring-a-quantum-computers-power-just-got-faster-and-more-accurate/
Tomi Engdahl says:
Tardigrade is first multicellular organism to be quantum entangled
https://www.newscientist.com/article/2302337-tardigrade-is-first-multicellular-organism-to-be-quantum-entangled/
Tomi Engdahl says:
Quantum Computing Breakthrough: Exotic Quantum Particles – Less Magnetic Field Required
https://scitechdaily.com/quantum-computing-breakthrough-exotic-quantum-particles-less-magnetic-field-required/
Tomi Engdahl says:
China’s New Quantum Computer Has 1 Million Times the Power of Google’s
https://www.scientiststudy.com/2021/10/chinas-new-quantum-computer-has-1.html
Tomi Engdahl says:
Quantum Computer Can Now Automatically Correct Errors In Major Breakthrough
https://www.iflscience.com/technology/quantum-computer-can-now-automatically-correct-errors-in-major-breakthrough/
Tomi Engdahl says:
Quantum Computing Sets Stage For Significant Scientific Breakthroughs
https://www.investors.com/news/technology/quantum-computing-sets-stage-for-major-breakthroughs/
Tomi Engdahl says:
Important Milestone Reached in Quantum Computing With Error Correction
https://scitechdaily.com/important-milestone-reached-in-quantum-computing-with-error-correction/
Tomi Engdahl says:
A potential hangup for quantum computing: Cosmic rays
For quantum chips, the problems they cause are too big for error correction.
https://arstechnica.com/science/2021/12/cosmic-rays-can-swamp-error-correction-on-quantum-processors/
Recently, when researchers were testing error correction on Google’s quantum processor, they noted an odd phenomenon where the whole error-correction scheme would sporadically fail badly. They chalked this up to background radiation, a combination of cosmic rays and the occasional decay of a naturally occurring radioactive isotope.
It seemed like a bit of an amusing aside at the time—Google having accidentally paid for an extremely expensive cosmic ray detector. But the people behind the processor took the problem very seriously and are back with a new paper that details exactly how the radiation affects the qubits. And they conclude that the problems caused by cosmic rays happen often enough to keep error-corrected quantum computations from working unless we figure out a way to limit the rays’ impact.
It’s a shame about the rays
Cosmic rays and radioactivity cause problems for classical computing hardware as well. That’s because classical computers rely on moving and storing charges, and cosmic rays can induce charges when they impact a material. Qubits, by contrast, store information in the form of the quantum state of an object—in the case of Google’s processor, a loop of superconducting wire linked to a resonator. Cosmic rays affect these, too, but the mechanism is completely different.
Tomi Engdahl says:
Quantum processor swapped in for a neural network
Quantum processor used to model weather based on sparse data.
https://arstechnica.com/science/2021/12/quantum-processor-swapped-in-for-a-neural-network/
Tomi Engdahl says:
Quantum computing could eat bitcoin for lunch but regulation can save it
https://www.cnbctv18.com/cryptocurrency/quantum-computing-could-eat-bitcoin-for-lunch-but-regulation-can-save-it-11736362.htm
The rapid advances in quantum computing – the computing industry says mainstream quantum computers are less than a decade away – means regulation will be needed to protect cryptocurrencies such as bitcoin
Backers of cryptocurrencies tout the digital tokens as the next evolution of currencies, pointing to the security features they offer.
But experts say advances in quantum computing, which is poised to increase computing power by more than a thousandfold, could make light work of the security features of cryptocurrencies, upending the technology that many believe will disrupt finance.
This technology, known as blockchain, works on a decentralised register – with millions of computers coming together to validate transactions.
The process of validation, also called mining, uses immense power as computers rely on brute force to make complex calculations.
But quantum computers, which use concepts from physics to process problems at a speed exponentially faster than conventional computers, could change the way cryptocurrencies work – for better or for worse.
Here’s the worst-case scenario: a user with a quantum computer could easily break the encryption associated with cryptocurrency transactions allowing them to impersonate someone else on the network.
“When the cryptography is broken, users could be losing their funds and the whole system will break,” Dawn Song, an entrepreneur and professor at the University of California, Berkeley, told the Collective
In 2019, Google created Sycamore, a 54-qubit quantum computer. (A qubit is the unit of power on a quantum computer.) Sycamore took 200 seconds to solve a series of complex calculations that would have taken 10,000 years for the most powerful conventional supercomputer to crack.
Recently, IBM unveiled the Eagle , a 127-qubit quantum computer.
It is not that the cryptocurrency industry is not aware of the threat posed by quantum computing.
For instance, makers of Ethereum, the world’s second-largest cryptocurrency, are working on developing what is called “post-quantum computing technology”.
Post-quantum computing technology is an upgrade spearheaded by the US government’s National Institute of Standards and Technology (NIST). Experts say the upgrade is as massive as fixing the Y2K problem or upgrading the Internet from IPv4 to IPv6.
Regulation for cryptocurrency is still being firmed up in many countries, including India.
But as it is with technology, it will have to keep pace with evolving scenarios.
For instance, as a CNET article points out, the very decentralised nature of cryptocurrencies could work against them when it comes to quantum computing.
Major changes to any crypto blockchain require the permission of more than half of the users on the network.
Tomi Engdahl says:
How fast can quantum computers process information? – study
https://www.jpost.com/science/article-689720
Quantum computers, unlike their conventional counterparts, use quantum mechanics to process information, which enables them to solve a wider range of problems – but there are still limits.
Tomi Engdahl says:
https://semiengineering.com/week-in-review-design-low-power-177/?cmid=51b37b55-b1b1-490c-aa51-659c8bf1e90e
Quantum computing
Sandia National Laboratories proposed a new benchmark for quantum computers to predict how likely it is that a quantum processor will run a specific program without errors. The researchers said that conventional benchmark tests underestimate many quantum computing errors, which can lead to unrealistic expectations of how powerful or useful a quantum machine is. “Our benchmarking experiments revealed that the performance of current quantum computers is much more variable on structured programs” than was previously known, said Timothy Proctor, a member of Sandia’s Quantum Performance Laboratory. “By applying our method to current quantum computers, we were able to learn a lot about the errors that these particular devices suffer — because different types of errors affect different programs a different amount.”
QuTech researchers are working on improved error correction for quantum computers. Based on the theory that by increasing the redundancy and using more and more qubits to encode data, the net error goes down. They designed a logical qubit consisting of seven physical qubits. “We show that we can do all the operations required for computation with the encoded information. This integration of high-fidelity logical operations with a scalable scheme for repeated stabilization is a key step in quantum error correction,” said Prof Barbara Terhal of QuTech. Prof Leonardo DiCarlo of QuTech added, “Our grand goal is to show that as we increase encoding redundancy, the net error rate actually decreases exponentially. Our current focus is on 17 physical qubits and next up will be 49. All layers of our quantum computer’s architecture were designed to allow this scaling.”
Tomi Engdahl says:
Quantum Computing for the Discovery of Materials
https://www.eeweb.com/quantum-computing-for-the-discovery-of-materials/?utm_source=newsletter&utm_campaign=link&utm_medium=EEWebEngInsp-20211223
Quantum computing has the potential to disrupt almost all industries, with exponential increases in performance compared to classical computing. The interest in quantum computing comes from the considerable amount of computing potential in quantum bits (qubits), which are exceedingly difficult to manage, both in terms of quantity and quality.
OTI Lumionics is implementing quantum methods to improve its Materials Discovery Platform that applies state of the art high-performance computing (HPC) simulations along with machine learning (ML) algorithms to design production-ready advanced materials without a wet-lab.
The platform provides faster material simulations, more accurate property predictions, mapping of excited states, and modeling of chemical reactions.
Over the past year, OTI has demonstrated its ability to simulate commercially relevant dimensional problems, such as the light-emitting metal complexes used in OLED displays, by using quantum methods. In an interview with EEWeb, Michael Helander, CEO at OTI, stated how OTI’s latest results show that quantum methods can exceed the capabilities of traditional simulations when run on both quantum hardware and quantum-inspired systems. OTI is now working to package these algorithms into a general purpose quantum computational chemistry tool.
Tomi Engdahl says:
China’s New Quantum Computer Has 1 Million Times the Power of Google’s
https://www.scientiststudy.com/2021/10/chinas-new-quantum-computer-has-1.html?m=1
In July this year, a team in China demonstrated that it has the world’s most powerful quantum computer, finally leapfrogging Google, who claimed to have achieved quantum supremacy back in 2019. Back then, China was touting a super-advanced 66-qubit quantum supercomputer called “Zuchongzhi” as a contender against Google’s 54-qubit Sycamore processor. But while Google’s quantum computers have not progressed noticeably since then, China on the other hand never slowed down, coming up with more powerful quantum processors.
According to a recent study published in peer-reviewed journal Physical Review Letters and Science Bulletin, physicists in China claim they’ve constructed two quantum computers with performance speeds that far outrival competitors in the US or indeed anywhere in the world — debuting a superconducting machine along with a speedier unit that uses light photons to obtain unprecedented results.
Jiuzhang 2 is actually an upgrade of a machine built by Pan’s team last year, uses photons, each one carrying a qubit – the basic unit of quantum information. Lead scientist with the Jiuzhang project, Lu Chaoyang highlighted that they “have increased the number of photons from 76 to 113, (the new machine) is billions of billions of times faster than supercomputers.”
Tomi Engdahl says:
Research Opens the Door to Fully Light-Based Quantum Computing
By Francisco Pires published 2 days ago
https://www.tomshardware.com/news/research-opens-the-door-to-fully-light-based-quantum-computing
Hailed as the fastest road towards deployable quantum computing systems.
Tomi Engdahl says:
https://scitechdaily.com/creating-the-heart-of-a-quantum-computer-developing-qubits/
Tomi Engdahl says:
New Standards Rolling Out for Clocking Quantum Computer Performance “Mirror circuits” one of new quantum benchmarks to quantify just how fast is fast
https://spectrum.ieee.org/quantum-computer-benchmarks?share_id=6848950
A quantum computer with great enough complexity—for instance, enough components known as quantum bits or “qubits”—could theoretically achieve a quantum advantage where it can find the answers to problems no classical computer could ever solve. In principle, a quantum computer with 300 qubits fully devoted to computing (not error correction) could perform more calculations in an instant than there are atoms in the visible universe.
Tomi Engdahl says:
Quantum technology: how it works, applications and why the US and China are racing to achieve supremacy
https://www.scmp.com/news/china/science/article/3161830/quantum-technology-how-it-works-applications-and-why-us-and
Tomi Engdahl says:
https://scitechdaily.com/integrated-photonic-circuits-for-quantum-technologies/
Tomi Engdahl says:
https://www.analyticsinsight.net/light-based-computer-chips-replacing-electrons-with-photons/
Tomi Engdahl says:
Innovative New Algorithms Advance the Computing Power of Early-Stage Quantum Computers
TOPICS:AlgorithmAmes LaboratoryDOEQuantum Computing
https://scitechdaily.com/innovative-new-algorithms-advance-the-computing-power-of-early-stage-quantum-computers/
Tomi Engdahl says:
https://hackaday.com/2022/01/19/arduino-meets-quantum-computer/
Connecting a Quantum Computer to an Arduino
https://www.youtube.com/watch?v=EFZnrl4wkT0
Tomi Engdahl says:
Major Breakthrough As Quantum Computing in Silicon Hits 99% Accuracy
https://scitechdaily.com/major-breakthrough-as-quantum-computing-in-silicon-hits-99-accuracy/
UNSW Sydney-led research paves the way for large silicon-based quantum processors for real-world manufacturing and application.
Australian researchers have proven that near error-free quantum computing is possible, paving the way to build silicon-based quantum devices compatible with current semiconductor manufacturing technology.
“Today’s publication in Nature shows our operations were 99 percent error-free,” says Professor Andrea Morello of UNSW, who led the work.
“When the errors are so rare, it becomes possible to detect them and correct them when they occur. This shows that it is possible to build quantum computers that have enough scale, and enough power, to handle meaningful computation.”
Quantum computing in silicon hits the 99% threshold
Morello’s paper is one of three published today in Nature that independently confirm that robust, reliable quantum computing in silicon is now a reality. This breakthrough features on the front cover of the journal.
Morello et al achieved 1-qubit operation fidelities up to 99.95 percent, and 2-qubit fidelity of 99.37 percent with a three-qubit system comprising an electron and two phosphorous atoms, introduced in silicon via ion implantation.
A Delft team in the Netherlands led by Lieven Vandersypen achieved 99.87 percent 1-qubit and 99.65 percent 2-qubit fidelities using electron spins in quantum dots formed in a stack of silicon and silicon-germanium alloy (Si/SiGe).
A RIKEN team in Japan led by Seigo Tarucha similarly achieved 99.84 percent 1-qubit and 99.51 percent 2-qubit fidelities in a two-electron system using Si/SiGe quantum dots.
Tomi Engdahl says:
European Milestone: Quantum Computer With More Than 5,000 Qubits Launched
https://scitechdaily.com/european-milestone-quantum-computer-with-more-than-5000-qubits-launched/
Official launch marks a milestone in the development of quantum computing in Europe.
A quantum annealer with more than 5,000 qubits has been put into operation at Forschungszentrum Jülich. Representatives from politics and science launched the company’s first cloud-based quantum D-Wave system outside North America.
The new quantum system is the second D-Wave quantum computer to be used within the JUNIQ user infrastructure and is the world’s first Advantage quantum annealer to be located outside the company’s home country, Canada.