Logical qubits start outperforming physical qubits
Quantinuum closes in on breakeven point in quantum error correction
Broomfield, Colorado, August 4th, 2022 — Quantinuum researchers have hit a significant milestone by entangling logical qubits in a fault-tolerant circuit using real-time quantum error correction. The research, published in a new scientific paper that was released on August 3rd, is the first experimental comparison study of different quantum error correction codes in similar environments and presents a collection of several different experiments. These experiments include:
- The first demonstration of entangling gates between two logical qubits done in a fully fault-tolerant manner using real-time error correction
- The first demonstration of a logical entangling circuit that has higher fidelity than the corresponding physical circuit.
This milestone achievement is important because it marks the first time that logical qubits have been shown to outperform physical qubits — a critical step towards fault-tolerant quantum computers.
“Quantinuum’s trapped-ion quantum computing roadmap is designed around continuous upgrades, enabled our flexible architecture and our precision control capabilities. This combination provides for outstanding, first-of-its-kind achievements that help accelerate the entire industry,” said Tony Uttley, President and COO of Quantinuum.
David Hayes, a Theory and Architecture Technical Manager at Quantinuum and co-author of the new research paper, said the research moves quantum computing closer to the point where encoded circuits outperform more primitive operations.
“People have worked with error corrected qubits before, but they haven't reached this sort of special point where the encoded operation is working better than the primitive operation,” Hayes said. “The other thing that's new here is that in other experiments we're doing the error correction while we're doing the operations. An important next step for us is to get the error rate induced by the error correction itself down further."
The findings are described in the new research paper, “Implementing Fault-tolerant Entangling Gates on the Five-Qubit code and the Color Code”. The paper was recently published on the arXiv. Scientists used both the H1-1 and the H1-2 quantum computers, Powered by Honeywell, to compare the Five-Qubit error code and the Distance Three Color Code in these tests.
Quantum researchers are in the early days of experimental quantum error correction with a multitude of codes to test. Quantinuum researchers can explore a wider range of quantum error codes, compared to other quantum hardware designs, due to the architecture of the machine.
The System Model H1 uses a trapped-ion design and a quantum charged coupled device architecture (QCCD). Along with the inherent flexibility of this design, another strength is all-to-all connectivity. All the qubits are connected to each other which makes it easy to move information through chains of ions without creating multiple errors along the way.
“Instead of having to build a new machine every time we want to try a new code, we can just program the machine to run a different code, make the measurements and weigh the different pros and cons,” Hayes said.
Advancing quantum error correction
All forms of technology need error correction including servers in data centers and space probes sending transmissions back to Earth. For Quantinuum and other companies in the quantum computing sector, quantum error correction is one of the most important pillars of progress. Errors prevent quantum computers from producing reliable results before they are overwhelmed. Quantinuum’s researchers are working toward the milestone of fault tolerance, meaning the errors can be suppressed to arbitrarily low levels.
Natalie Brown, another co-author of the paper and an Advanced Physicist at Quantinuum, said that most classical error correction principles fail with quantum computers because of the basic nature of quantum mechanics.
“It becomes very difficult to suppress noise to very small levels, and that becomes a problem in quantum computing,” she said. “The most promising candidate was this quantum error correction, where we take the physical qubits, make a logical qubit.”
Logical qubits are groups of physical qubits working together to perform a computation. For each physical qubit used in a computation, other ancillary qubits perform a range of tasks such as spotting and correcting errors as they occur.
Ciaran Ryan-Anderson, a Senior Advanced Physicist at Quantinuum and also a co-author of the new paper, said the newest research paper builds on research performed in 2021 and published in Physical Review X. That work explained how researchers at Honeywell Quantum Solutions applied multiple rounds of quantum error correction to a single logical qubit.
“One of the first really important things to demonstrate was these repeated rounds of quantum error correction cycles,” he said.
That is one of several milestones on Ryan-Anderson’s quantum error correction checklist:
- Conduct repeated rounds of fault tolerant quantum error correction
- Feed forward and conditionally apply syndrome extraction
- Enable real-time determination of correction for a quantum error correction code
- Demonstrate general algorithmic real-time decoding
- Scale up quantum error correction with two logical qubits
- Hit the breakeven point when logical quantum computing starts to outperform physical quantum computing
“Quantinuum has achieved some of the milestones required to accomplish this now,” Ryan-Anderson said.
Five-Qubit Code vs. Color Code
Building upon the 2021 research involving one logical qubit, the newest research illustrates the Quantinuum team’s progress with quantum error correction and two logical qubits. The team tested two error codes familiar to quantum experts: the Five-Qubit Code and the Color Code. The Five-Qubit Code does not allow for a fault tolerant transversal gate using only two logical qubits. Researchers used “pieceable” fault tolerance to decompose an initially non-fault tolerant logical gate operation into pieces that are individually fault-tolerant. The Color Code, however, does allow the use of a transversal CNOT gate which is naturally fault-tolerant.
How the experiment worked
H1-2 can use up to 12 qubits and H1-1 can use up to 20. The Five-Qubit Code tested on H1-2 while the Color Code tested on H1-1. Both computers use the same surface electrode ion trap to control ytterbium ions as qubits. Ion transport to isolated gate zones with focused laser beams provides low crosstalk gate and mid-circuit measurement operations.
The researchers ran five experiments with different combinations of circuit elements to test the Five-Qubit Code and to understand the impact of fault tolerant design and circuit depth. The team found that the extra circuitry designed to increase fault tolerance had a negative impact on the overall fidelity of the logical operation, due to the large number of CNOT operations required.
The Color Code showed much better results due in part to the ability to use a transversal CNOT gate. The team ran seven experiments to investigate the fault tolerant potential of these codes. With the Color Code, the researchers found that the State Preparation and Measurement circuits benefitted from the addition of fault tolerant circuitry with a significant reduction of error rates: 99.94% for the logical qubits compared to 99.68% for the physical qubits. This was the only additional circuitry required to make the circuit fault tolerant from end-to-end, since the logical CNOT is transversal and naturally fault tolerant.
The researchers concluded that the “relatively economical fault tolerant circuitry of the Color Code will provide a better platform for computation than the qubit efficient five-qubit code.” Also, the researchers found that the Five-Qubit Code would be useful only in systems with far lower physical error rates than quantum computers have at this point in time.
Hayes said the team’s next step will be to surpass the breakeven point and provide proof of the work. “We are getting evidence that we're really darn close to that point, but there's a lot of work that needs to be done to actually prove it,” he said. “Just getting right there is not good enough, you have to actually get past it.”
A new classical+quantum connection
Another advance from this experiment is a new classical processor with enhanced capabilities which will be essential to scalable algorithmic decoders. The data from the classical functions were used to dictate the control flow and operations executed in the quantum program.
The decoders used in these experiments were partially written in Rust and compiled to WebAssembly (Wasm). The choice of Wasm provides an efficient, safe, and portable classical language to have functions that are callable from quantum programs.
The decoder implemented in Rust uses many high-level program constructs. The support for these features means that various scalable algorithmic decoders can be ergonomically implemented in various high-level languages that compile to Wasm (such as Rust, C, and C++) and called from quantum programs.
“It was pretty enabling for this particular experiment, and it'll be even more important for future experiments as these things get more and more complicated,” Hayes said.
Another advantage of the trapped ion architecture is the ability to do real-time decision making during the execution of the quantum circuit thanks to long coherence times and the ability to do mid-circuit measurement and reset qubits as needed.
“Our systems have very long coherence times which is super advantageous when integrating in the classical compute real-time decision making,” Hayes said.
The Honeywell Trademark is used under license from Honeywell International Inc. Honeywell International Inc. makes no representations or warranties with respect to this product. This product is produced by Quantinuum.
About Quantinuum
Quantinuum, the world’s largest integrated quantum company, pioneers powerful quantum computers and advanced software solutions. Quantinuum’s technology drives breakthroughs in materials discovery, cybersecurity, and next-gen quantum AI. With over 500 employees, including 370+ scientists and engineers, Quantinuum leads the quantum computing revolution across continents.
Broomfield, Colorado, November 19th, 2024 – Quantinuum, the world’s largest and leading integrated quantum computing company, has been recognized by Fast Company as a winner in the 2024 Next Big Things in Tech Awards in the Computing, Chips, and Foundational Technology category. In its fourth year, the list honors technology breakthroughs that promise to shape the future of our society. This prestigious accolade underscores Quantinuum’s advancements with its System Model H2 quantum processor, the latest in a series of groundbreaking announcements.
Quantinuum’s H2 Quantum Processor: A Breakthrough in Quantum Computing
Launched in 2023 and upgraded in 2024, the H2 quantum processor represents a major advancement in quantum computing. As the most benchmarked system with the highest quantum volume in the industry, H2 is a testament to Quantinuum’s path in leading the world to universal, fully fault tolerant quantum computing future.
"The System Model H2 represents a significant leap in computing, demonstrating capabilities that can no longer be fully simulated by classical computers." said Dr. Rajeeb Hazra, President & CEO of Quantinuum. "Its unique design has led to significant achievements, including the creation of 12 reliable logical qubits and a 100-fold enhancement in a key quantum computing benchmark, Random Circuit Sampling (RCS). These results have made our systems integral to hybrid quantum computing workflows, combining our high performing quantum systems with leading AI and HPC solutions.”
These innovations have the potential to revolutionize fields like chemistry, drug discovery, and financial forecasting, demonstrating the far-reaching implications of Quantinuum's work.
Roadmap to Universal, Fully Fault Tolerant Quantum Computing
Quantinuum recently unveiled its accelerated roadmap to achieve universal fault-tolerant quantum computing in 2029. This integrated path not only emphasizes hardware advancements but also focuses on critical software capabilities that are essential for delivering full-stack quantum computing and hybrid quantum computing solutions.
Quantinuum’s next system, Helios, will launch in 2025 with 96 qubits and will help to unlock scientific advances that will surpass classical computing results.
About Quantinuum
Quantinuum, the world’s largest integrated quantum computing company, pioneers powerful quantum computers and advanced software solutions. Quantinuum’s technology drives breakthroughs in materials discovery, cybersecurity, and next-gen quantum AI. With over 500 employees, including 370+ scientists and engineers, Quantinuum leads the quantum computing revolution across continents.
- Companies aim at developing powerful ion traps for Quantinuum’s future generations of quantum computers.
- Infineon provides expertise in process development, fabrication, and quantum processing unit (QPU) technology
- Partnership to drive progress in fields such as generative chemistry, material science, and artificial intelligence.
Neubiberg, Germany and Broomfield, Colorado, USA, 19 November 2024 – Infineon Technologies AG, a global leader in semiconductor solutions, and Quantinuum, a global leader in integrated, full-stack quantum computing, today announced a strategic partnership to develop the future generation of ion traps. This partnership will drive the acceleration of quantum computing and enable progress in fields such as generative chemistry, material science, and artificial intelligence.
“We are thrilled to partner with Quantinuum, a leader in quantum computing, to push the boundaries of quantum computing and generate larger, more powerful machines that solve meaningful real-life problems," said Richard Kuncic, Senior Vice President and General Manager Power Systems at Infineon Technologies. “This collaboration brings together Infineon's state-of-the-art knowledge in process development, fabrication, and quantum processing unit (QPU) technology with Quantinuum's cutting-edge ion-trap design expertise and experience with operating high-performance commercial quantum computers.”
Infineon innovates with a dedicated team to make their trapped-ion quantum processing units (QPUs) the heart of the leading quantum computers. The company has invested in this field since 2017, applying its expertise in high-volume processing technologies and developing technologies, like integrated photonics and control electronics, to enable their partners to scale the qubit count of their machines.
In Quantinuum’s hardware approach, charged atoms are trapped with electromagnetic fields so they can be manipulated and encoded with information using microwave signals and lasers. This design has distinct advantages over other quantum hardware, including higher fidelities and longer coherence times.
This collaboration builds on today’s leading performance of Quantinuum's trapped-ion quantum computers, which currently hold the world records in key performance benchmarks such as 2-qubit gate fidelity, quantum volume and cross-entropy benchmark fidelity. To deliver even better fidelity at greater scale and achieve commercial advantage, larger and more sophisticated ion traps are needed. Engineers from the two companies have been working together for more than a year and will intensify their efforts under the current partnership to develop powerful ion traps for Quantinuum’s next-generation quantum computers.
“At Quantinuum, our mission is to accelerate useful quantum computing. We have announced a roadmap to reach universal fault-tolerance in 2029. Our partnership with Infineon is key to our delivering on this commitment,“ said Dr. Rajeeb Hazra, President and CEO of Quantinuum.
About Quantinuum
Quantinuum, the world’s largest integrated quantum computing company, pioneers powerful quantum computers and advanced software solutions. Quantinuum’s technology drives breakthroughs in materials discovery, cybersecurity, and next-gen quantum AI. With over 500 employees, including 370+ scientists and engineers, Quantinuum leads the quantum computing revolution across continents.
For more information, please visit the website at www.quantinuum.com
About Infineon
Infineon Technologies AG is a global semiconductor leader in power systems and IoT. Infineon drives decarbonization and digitalization with its products and solutions. The Company had around 58,060 employees worldwide (end of September 2024) and generated revenue of about €15 billion in the 2024 fiscal year (ending 30 September). Infineon is listed on the Frankfurt Stock Exchange (ticker symbol: IFX) and in the USA on the OTCQX International over-the-counter market (ticker symbol: IFNNY).
For more information, please visit the website at www.infineon.com
- First successful delivery of quantum tokens using commercial QKD hardware, demonstrating fast transaction verification at the point of exchange - a crucial step toward quantum-enhanced financial security and a major advance for QKD.
- Quantum tokens are designed to provide unforgeability, privacy, and fast settlement, in a single financial instrument. No previous technology can deliver these three combined benefits.
- In the world’s first implementation using off-the-shelf hardware, quantum tokens were transmitted across 10km of fibre in Tokyo, using commercial quantum key distribution (QKD) devices provided by NEC*.
- This is a pivotal step towards the deployment of ultra-high-security quantum tokens in use cases such as tokenized asset security and high-speed trading.
Tokyo, Japan and Broomfield, Colorado - November 18th, 2024 – In a long anticipated trial, Quantinuum ("Quantinuum", Head Office: Broomfield, Colorado, U.S.A., CEO: Rajeeb Hazra), together with Mitsui & Co., Ltd. ("Mitsui", Head Office: Tokyo, President and CEO: Kenichi Hori) and NEC ("NEC", Head Office: Tokyo, President and CEO: Takayuki Morita) today announced the successful delivery of quantum tokens across a 10km fibre-optic network in Japan. This is the first time such a delivery has been accomplished.
Quantum tokens are a new financial instrument that take advantage of the properties of quantum physics to meet the robust demands of asset trading without the communication overheads required by traditional financial systems. Quantum tokens are transmitted across fibre-optic quantum key distribution (QKD) networks, which are rapidly expanding around the globe. Today's announcement with Mitsui demonstrates growing industry recognition of quantum tokens' potential in financial services.
Ilyas Khan, Founder and Chief Product Officer at Quantinuum, said: “The original motivation for quantum communications was the exchange of money, as envisaged by Stephen Wiesner. Today, we have demonstrated real-world security enhancements for financial systems using off-the-shelf quantum communications hardware. This opens the door to a new era in quantum-enhanced security with wide applicability, providing commercial organisations with something concrete to utilise.”
Koji Naniwada, Deputy General Manager, Quantum Innovation Dept. at Mitsui, said: “Quantum tokens will increase the security of digital assets, while improving transaction performance and maintaining privacy. These topics are critical for our customers and partners in the financial sector and this demonstration is a valuable outcome of our partnership with Quantinuum.”
Naoki Ishida, Director with the Trading and Service Solution Department at NEC, said: “We are the first to provide a platform for realizing a quantum token system using NEC’s quantum key distribution (QKD) devices. Based on the results of this trial between Mitsui & Co. and Quantinuum, we will continue to work towards the social implementation of quantum cryptography technology.”
Quantum tokens are designed to use quantum physics to prevent forgery, while ensuring transactions can be settled near-instantly, whereas traditional payments systems rely on double-entry bookkeeping to prevent double-spending of funds. This adds time, overhead and risk to every transaction, as digital systems are consulted to confirm funds are available and to settle transactions.
Quantum tokens instead rely on the no-cloning theorem of quantum physics to prevent forgeries and double-spending. Only the intended recipient will receive the correct token data, which can only be spent at one location in the future. This enables near-instant transaction settlement by removing the need to check multiple systems or wait for network confirmations.
As demonstrated in Quantinuum’s recent work with HSBC, securing digital assets in the quantum-age is growing in urgency. The financial sector is increasingly looking to quantum technology to solve these complex problems with the power of nature.
Learn more about this new frontier of financial security, powered by quantum, in our whitepaper.
***
Note:
(*) The equipment provided by NEC was partially supported by results from Japan’s Ministry of Internal Affairs and Communications’ (MIC) “Research and development for construction of a global quantum cryptography network”(JPJ008957) under “R&D of ICT Priority Technology Project” (JPMI00316) and Japan’s Cabinet Office’s "Photonics and Quantum Technology for Society 5.0" project under the Cross-ministerial Strategic Innovation Promotion Program (SIP).
About Mitsui
Mitsui & Co. is a global trading and investment company with a presence in more than 60 countries and a diverse business portfolio covering a wide range of industries.
The company identifies, develops, and grows its businesses in partnership with a global network of trusted partners including world leading companies, combining its geographic and cross-industry strengths to create long-term sustainable value for its stakeholders.
Mitsui has set three key strategic initiatives for its current Medium-term Management Plan: supporting industries to grow and evolve with stable supplies of resources and materials, and providing infrastructure; promoting a global transition to low-carbon and renewable energy; and empowering people to lead healthy lives through the delivery of quality healthcare and access to good nutrition.
Visit https://www.mitsui.com/jp/en/index.html for more information.
About Quantinuum
Quantinuum, the world’s largest integrated quantum company, pioneers powerful quantum computers and advanced software solutions. Quantinuum’s technology drives breakthroughs in materials discovery, cybersecurity, and next-gen quantum AI. With over 500 employees, including 370+ scientists and engineers, Quantinuum leads the quantum computing revolution across continents.
About NEC Corporation
NEC Corporation has established itself as a leader in the integration of IT and network technologies while promoting the brand statement of “Orchestrating a brighter world.” NEC enables businesses and communities to adapt to rapid changes taking place in both society and the market as it provides for the social values of safety, security, fairness and efficiency to promote a more sustainable world where everyone has the chance to reach their full potential. For more information, visit NEC at http://www.nec.com.