In experiments performed at the University of Wisconsin-Madison, researchers found that fluctuations in the electrical charge of multiple quantum bits, or qubits, can be highly correlated, as opposed to completely random and independent. The team also linked tiny error-causing perturbations in the qubits charge state to the absorption of cosmic rays. Credit: Illustration courtesy of UW-Madison
Research by aLawrence Livermore National Laboratory(LLNL) physicist and a host of collaborators is shedding new light on one of the major challenges to realizing the promise and potential of quantum computing error correction.
In a new paperpublished inNatureand co-authored by LLNL physicist Jonathan DuBois, scientists examined quantum computing stability, particularly what causes errors and how quantum circuits react to them. This must be understood in order to build a functioning quantum system. Other co-authors included researchers at theUniversity of Wisconsin-Madison,Fermi National Accelerator Laboratory, Google,Stanford Universityand international universities.
In experiments performed at UW-Madison, the research team characterized a quantum testbed device, finding that fluctuations in the electrical charge of multiple quantum bits, or qubits the basic unit of a quantum computer can be highly correlated, as opposed to completely random and independent. When a disruptive event occurs, such as a burst of energy coming from outside the system, it can affect every qubit in the vicinity of the event simultaneously, resulting in correlated errors that can span the entire system, the researchers found. Additionally, the team linked tiny error-causing perturbations in the qubits charge state to the absorption of cosmic rays, a finding that already is impacting how quantum computers are designed.
For the most part, schemes designed to correct errors in quantum computers assume that the errors across qubits are uncorrelated theyre random. Correlated errors are very difficult to correct, said co-author DuBois, who heads LLNLs Quantum Coherent Device Physics (QCDP) Group. Essentially, what this paper is showing is that if a high-energy cosmic ray hits the device somewhere, it has the potential to affect everything in the device at once. Unless you can prevent that from happening you cant perform error correction efficiently, and youll never be able to build a working system without that.
Unlike bits found in classical computers, which can exist only in binary states zeroes or onesthe qubits that make up a quantum computer can exist in superpositions. For a few hundred microseconds, data in a qubit can be either a one or zero before being projected into a classical binary state. Whereas bits are only susceptible to one type of error, under their temporary excited charge state, the delicate qubits are susceptible to two types of error, stemming from changes that can occur in the environment.
Charged impulses, even minute ones like those from cosmic rays absorbed by the system, can create a blast of (relatively) high-energy electrons that can heat up the quantum devices substrate just long enough to disrupt the qubits and disturb their quantum states, the researchers found. When a particle impact occurs, it produces a wake of electrons in the device. These charged particles zoom through the materials in the device, scattering off atoms and producing high-energy vibrations and heat. This alters the electric field as well as the thermal and vibrational environment around the qubits, resulting in errors, DuBois explained.
Weve always known this was possible and a potential effectone of many that can influence the behavior of a qubit, DuBois added. We even joked when we saw bad performance that maybe its because of cosmic rays. The significance of this research is that, given that sort of architecture, it puts some quantitative bounds on what you can expect in terms of performance for current device designs in the presence of environmental radiation.
To view the disruptions, researchers sent radio frequency signals into a four qubit system and, by measuring their excitation spectrum and performing spectroscopy on them, were able to see the qubits flip from one quantum state to another, observing that they all shift in energy at the same time, in response to changes in the charge environment.
If our model about particle impacts is correct, then we would expect that most of the energy is converted into vibrations in the chip that propagate over long distances, said UW-Madison graduate student Chris Wilen, the papers lead author. As the energy spreads, the disturbance would lead to qubit flips that are correlated across the entire chip.
Using the method, researchers also examined the lifetimes of qubits the length of time that qubits can remain in their superposition of both one and zero and correlated changes in the charge state with a reduction in lifetime of all the qubits in the system.
The team concluded that quantum error correction will require development of mitigation strategies to protect quantum systems from correlated errors due to cosmic rays and other particle impacts.
I think people have been approaching the problem of error correction in an overly optimistic way, blindly making the assumption that errors are not correlated, said UW-Madison physics professor Robert McDermott, senior author on the study. Our experiments show absolutely that errors are correlated, but as we identify problems and develop a deep physical understanding, were going to find ways to work around them.
Though long theorized, DuBois said the teams findings had never been experimentally proven in a multi-qubit device before. The results will likely impact future quantum system architecture, such as putting quantum computers behind lead shielding or underground, introducing heatsinks or dampers to quickly absorb energy and isolate qubits, and alter the types of materials used in quantum systems.
LLNL currently has aquantum computing testbed system, designed and built with funding from a Laboratory Directed Research and Development (LDRD) Strategic Initiative that began in 2016. It is being developed with continued support by the National Nuclear Security Administrations Advanced Simulation & Computing program and its Beyond Moores Law project.
In related follow-on work, DuBois and his team in the QCDP group are studying a quantum device that is significantly less sensitive to the charge environment. At the extreme cold temperatures required by quantum computers (systems are kept at temperatures colder than outer space), DuBois said researchers observe that thermal and coherent energy transport is qualitatively different from room temperature. For example, instead of diffusing, thermal energy can bounce around in the system like sound waves.
DuBois said he and his team are focused on understanding the dynamics of the microscopic explosion that occurs inside quantum computing devices when they interact with high energy particles and developing ways to absorb the energy before it can disrupt the delicate quantum states stored in the device.
There are potentially ways to design the system so its as insensitive as possible to these kinds of events, and in order to do that you need to have a really good understanding of how it heats up, how it cools down and what exactly is happening through the whole process when exposed to background radiation, DuBois said. The physics of whats going on is quite interesting. Its a frontier, even aside from the quantum applications, because of the oddities of how energy is transported at those low temperatures. It makes it a physics challenge.
DuBois has been working with the papers principal investigator McDermott (UW-Madison)and his group to develop ways to use qubits as detectors to measure charge bias, the method the team used in the paper to conduct their experiments.
Reference: Correlated charge noise and relaxation errors in superconducting qubits by C. D. Wilen, S. Abdullah, N. A. Kurinsky, C. Stanford, L. Cardani, G. DImperio, C. Tomei, L. Faoro, L. B. Ioffe, C. H. Liu, A. Opremcak, B. G. Christensen, J. L. DuBois and R. McDermott, 16 June 2021, Nature.DOI: 10.1038/s41586-021-03557-5
The featured work, including DuBois contribution, was funded by a collaborative grant between LLNL and UW-Madisonfrom the U.S.Department of Energys Office of Science.
The paper included co-authors from UW-Madison, the Fermi National Accelerator Laboratory, the Kavli Institute for Cosmological Physics at the University of Chicago, Stanford University, INFN Sezione di Roma, Sorbonne Universites Laboratoire de Physique Theorique et Hautes Energies and Google.
- IonQ and University of Maryland Researchers Demonstrate Fault-Tolerant Error Correction, Critical for Unlocking the Full Potential of Quantum... - October 12th, 2021
- Quantum computing startups pull in millions as VCs rush to get ahead of the game - The Register - October 12th, 2021
- Zapata, University of Hull researchers take quantum computing to deep space - FierceElectronics - October 12th, 2021
- IBM and Raytheon Technologies collaborate on AI, cryptography and quantum technologies - Scientific Computing World - October 12th, 2021
- How science and diplomacy inform each other - SWI swissinfo.ch - swissinfo.ch - October 12th, 2021
- Digital Wealth Management Fees to Increase Threefold to $12.6 Billion By 2026 - Yahoo Finance - October 12th, 2021
- Is Neuromorphic Computing The Answer For Autonomous Driving And Personal Robotics? - Forbes - October 12th, 2021
- IonQ is set to make its public trading debut. Here's a look at the quantum computing company's 2021 highlights - Technical.ly DC - October 2nd, 2021
- Connecting the Dots Between Material Properties and Superconducting Qubit Performance - SciTechDaily - October 2nd, 2021
- Quantum Computing in Agriculture Market to Witness Stellar CAGR During the Forecast Period 2021 -2026 - Northwest Diamond Notes - October 2nd, 2021
- What is quantum computing? - September 21st, 2021
- Why quantum computing is a security threat and how to defend against it [Q&A] - BetaNews - September 21st, 2021
- 'This Is The Beginning Of A New Industry': College Park Looks To Quantum Computing To Spark Office Growth - Bisnow - September 21st, 2021
- Prepare for the next phase of digital transformation at The Quantum Computing Summit - UKTN - UKTN (UK Technology News - September 21st, 2021
- A Simple Equation Indicates Wormholes May Be the Key to Quantum Gravity - Interesting Engineering - September 21st, 2021
- Explore Trends and COVID-19 Impact on Quantum Computing Market 2021 Research Report and Industry Forecast till 2027 | Know More Stillwater Current -... - September 21st, 2021
- Australias nuclear submarines and AUKUS: The view from Jakarta - Brookings Institution - September 21st, 2021
- Research on Quantum Computing in Health Care Market 2021: By Growing Rate, Type, Applications, Geographical Regions, and Forecast to 2026 - Northwest... - September 15th, 2021
- Atomically-Thin, Twisted Graphene Has Unique Properties That Could Advance Quantum Computing - SciTechDaily - September 15th, 2021
- For The First Time, Scientists Have Entangled Three Qubits on Silicon - ScienceAlert - September 15th, 2021
- UChicago, Duality Teams to Pitch at 2021 Chicago Venture Summit - Polsky Center for Entrepreneurship and Innovation - Polsky Center for... - September 15th, 2021
- View: Its the Spacetime to Quantum - Economic Times - September 15th, 2021
- IonQ Scores Quantum Computing Deal With University Of Maryland And Announces Its Tripling 2021 Bookings - Forbes - September 11th, 2021
- How Horizon Plans To Bring Quantum Computing Out Of The Shadows - Forbes - September 11th, 2021
- Quantum Computing Breakthrough: Entanglement of Three Spin Qubits Achieved in Silicon - SciTechDaily - September 11th, 2021
- Quantum Computing Theorist Vojtech Vlcek Receives Research Award from DOE - HPCwire - September 11th, 2021
- UMD, IonQ join forces to create the nation's first quantum computing lab in College Park - The Diamondback - September 11th, 2021
- Quantum computing breakthrough achieved, road to the future begins now - TweakTown - September 11th, 2021
- Leading Chinese researchers are looking at the coming quantum revolution - The Press Stories - September 4th, 2021
- Top 10 Data Center Stories of the Month: August 2021 - Data Center Knowledge - September 4th, 2021
- Large-Scale Simulations Of The Brain May Need To Wait For Quantum Computers - Forbes - September 3rd, 2021
- NSA: We 'don't know when or even if' a quantum computer will ever be able to break today's public-key encryption - The Register - September 3rd, 2021
- IBM quantum computing: From healthcare to automotive to energy, real use cases are in play - TechRepublic - September 1st, 2021
- Quantum Computing in Manufacturing Market Rising Trends-Microsoft, D-Wave Solutions, Rigetti Computing, Intel UNLV The Rebel Yell - UNLV The Rebel... - September 1st, 2021
- Quantum computers could read all your encrypted data. This 'quantum-safe' VPN aims to stop that - ZDNet - August 30th, 2021
- Sumitomo Corporation Quantum Transformation (QX) Project Announces Its Vision and Activities at the IEEE Quantum AI Sustainability Symposium -... - August 30th, 2021
- Life, the universe and everything Physics seeks the future - The Economist - August 30th, 2021
- This Exotic Particle Had an Out-of-Body Experience These Surprised Scientists Took a Picture of It - SciTechDaily - August 30th, 2021
- Deloitte's quantum computing leader on the technology's healthcare future - Healthcare IT News - August 24th, 2021
- Urgent Warning Issued Over The Future Of Bitcoin Even As The Crypto Market Price Smashes Past $2 Trillion - Forbes - August 24th, 2021
- Sumitomo Corporation Quantum Transformation (QX) Project Announces Its Vision and Activities at the IEEE Quantum AI Sustainability Symposium - Yahoo... - August 24th, 2021
- Energy Department Sets $61M of Funding to Advance QIS Research - MeriTalk - August 24th, 2021
- Quantum Takes the Scenic Route in Automotive - The Next Platform - August 14th, 2021
- Quantum computing: How BMW is getting ready for the next technology revolution - ZDNet - August 10th, 2021
- Quantum Computing Tech is Amazing. But What Does Business Think? - DesignNews - August 10th, 2021
- AWS leverages Singapore scientists to overcome the hurdles facing quantum computing The Register - Illinoisnewstoday.com - August 10th, 2021
- Quantum Computing Market 2021 with Top Countries Data Analysis by Industry Trends, Size, Share and Company Overview - Digital Journal - August 10th, 2021
- 'Magic Angle' Graphene and How it Could be a Magnet-Proof Superconducter - AZoM - August 10th, 2021
- Healthcare technology development is being accelerated by the COVID-19 pandemic - Healthcare Finance News - August 10th, 2021
- From theory to reality: Google claims to created physics-defying 'time crystal' inside its quantum computer - Silicon Canals - August 6th, 2021
- Google says it has created a time crystal in a quantum computer, and it's weirder than you can imagine - ZDNet - August 6th, 2021
- T-Hub, HCL to collaborate on Quantum Computing and Deep Tech. - The Hindu - August 6th, 2021
- Google announces that it may have created a "time crystal" that breaks physics - Texasnewstoday.com - August 6th, 2021
- Why it's time to wake up to the quantum threat - Finextra - Finextra - Finextra - August 6th, 2021
- Quantum Computing Market 2021-2025Top Trends, Business Opportunity, and Growth Strategy The Manomet Current - The Manomet Current - August 6th, 2021
- Superconductivity Research: Researchers Develop New Material that Enables Quantum Information-Based Technology - Science Times - August 6th, 2021
- AI, quantum computing and other technologies poised to transform healthcare - Healthcare Finance News - August 5th, 2021
- Data Analytica Just Released Their New Quantum Computing Simulation Software - PR.com - August 5th, 2021
- Q-CTRL, University of Sydney Devise Machine Learning Technique Used to Pinpoint Quantum Errors - HPCwire - August 5th, 2021
- Q-CTRL: machine learning technique to pinpoint quantum errors - News - The University of Sydney - August 5th, 2021
- U.S. DoE sends another $ 73 million into the future of Quantum - Illinoisnewstoday.com - August 5th, 2021
- Harvard-led physicists have taken a major step in the competition with quantum computing - Illinoisnewstoday.com - July 18th, 2021
- Startup hopes the world is ready to buy quantum processors - Ars Technica - July 16th, 2021
- Covid isolation hits auto, Tom Tom's Virtual Horizon, BMW/Amazon quantum computing - the week - just-auto.com - July 16th, 2021
- Rigetti Computing Partners with Riverlane, Astex Pharmaceuticals to Advance Quantum Computing for Drug Discovery - Yahoo Finance - July 16th, 2021
- Quantum computing: This new 100-qubit processor is built with atoms cooled down near to absolute zero - ZDNet - July 10th, 2021
- This quantum computer with a 3D chip is heading into the cloud - ZDNet - July 10th, 2021
- French researchers on the verge of quantum computing milestone - RFI English - July 10th, 2021
- IBM partners with UK on $ 300 million quantum computing research initiative - Illinoisnewstoday.com - July 10th, 2021
- Quantum Computing Software Market worth $0.43 billion by 2026 - Exclusive Report by MarketsandMarkets - PRNewswire - July 10th, 2021
- African Education Minister Has Big Hi-Tech Dreams And Makes Music Videos Too : Goats and Soda - NPR - July 10th, 2021
- Why industry supports the government's $110 billion bet on technology R&D - Federal News Network - July 10th, 2021
- Quantum Computing Breakthrough: Unveiling Properties of New Superconductor - Analytics Insight - July 2nd, 2021
- The only answer to the quantum cybersecurity threat is quantum - Sifted - July 2nd, 2021
- Quantum computers are already detangling natures mysteries - Wired.co.uk - June 18th, 2021
- What Are the Quantum Computing Threats to Security? - Design and Reuse - Design and Reuse - June 18th, 2021
- Cutting-edge research into quantum computing: BMW Group and Technical University of Munich agree to create an endowed chair in Quantum Algorithms and... - June 18th, 2021
- Is quantum computing about to change the world? - BroadbandDeals - June 18th, 2021
- Clearing the way toward robust quantum computing - MIT News - June 16th, 2021
- Heres How Quantum Computers Will Really Affect Cryptocurrencies - Forbes - June 16th, 2021