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, CO, May 19th, 2026 — Quantinuum, a leading quantum computing company, today announced a strategic collaboration with Synopsys, a global leader in electronic design automation and engineering simulation, focused on the integration of quantum computing into the modern engineering toolkit to help overcome the “computational wall” believed to be limiting the pace of industrial innovation.
The Challenge: Designing for Accuracy in the Physical World
Modern industrial design depends on high-fidelity simulation to make better decisions earlier — potentially reducing costly prototypes, shortening development cycles, and improving product performance. Across aerospace and advanced electronics, teams rely on computational fluid dynamics (CFD) and electromagnetic simulation to predict real-world behavior before build and test.
However, as products become more complex, simulation workloads scale dramatically and can require computational resources that exceed the capabilities of even the most advanced classical supercomputers. As a result, engineers must increasingly balance simulation accuracy against runtime, cost and development speed. The collaboration between Quantinuum and Synopsys seeks to overcome these limitations by integrating quantum computing capabilities directly into advanced engineering workflows.
“Our goal is to turn quantum computing into a practical business advantage for the world’s most innovative companies,” said Dr. Rajeeb Hazra, President and CEO of Quantinuum. “By improving how these core design equations are solved, we aim to help innovators explore more accurate models and accelerate breakthroughs in materials and next-generation technologies.”
Transforming Industrial Design with Quantum Computing
The companies aim to build a scalable, end-to-end workflow that integrates quantum algorithms directly into existing industrial software and libraries. By combining the industry-leading accuracy[1] of Quantinuum’s systems with Synopsys’ deep expertise in engineering simulation and design tools, the partnership aims to make quantum computing a functional part of the modern engineering toolkit.
“This partnership is about giving innovators the tools they need to solve the world’s most difficult design challenges,” said Prith Banerjee, Senior Vice President of Innovation at Synopsys. “By integrating quantum computing into today's engineering workflows, we believe we can accelerate innovation while maintaining the standards and reliability that customers trust.”
The collaboration focuses on three key goals aimed at driving value for the engineering sector:
- Higher Accuracy for the Physical World: Enabling engineers to model critical physical details that were previously too costly for classical supercomputers to capture accurately.
- Faster and More Cost-Effective Simulations: Accelerating simulation timelines to help companies move from concept to prototype faster while significantly reducing R&D costs
- Greater Augmentation and Scale for Existing Workflows: Ensuring new quantum-native solvers maintain the rigorous validation standards and modeling intuition that industrial users demand.
By building on established CFD and electromagnetic capabilities, this effort aims to allow that as quantum computers scale, industrial engineers can explore future computational advantages without having to reinvent their design process. This approach builds on decades of validated engineering expertise while opening a new potential path alongside the new frontier for computing.
About Quantinuum
Quantinuum is a leading quantum computing company offering a full-stack platform designed to make quantum computing deployable in real-world environments. The company has commercially deployed multiple generations of quantum systems built on the well-established QCCD architecture, which it has implemented with novel designs and capabilities to achieve the industry’s highest accuracy levels based on average two-qubit gate fidelity.[2] Quantinuum has active engagements with market leaders across pharmaceuticals, material science, financial services, and government and industrial markets.
The company has a global workforce of approximately 700 employees, including top scientists and researchers. Over 70% of its technology team holds PhDs and Master’s degrees. Quantinuum’s headquarters is in Broomfield, Colorado, with additional facilities across the United States, United Kingdom, Germany, Japan, Qatar, and Singapore.
For more information, please visit www.quantinuum.com.
[1] Based on average two-qubit gate fidelity of 99.921% as of December 31, 2025.
[2] Based on average two-qubit gate fidelity of 99.921% as of December 31, 2025.
Source: PRNewswire - Honeywell
Charlotte, N.C., May 8th, 2026 — Honeywell (NASDAQ: HON) today announced that Quantinuum, a leading, full-stack quantum computing company, has publicly filed a registration statement on Form S-1 with the U.S. Securities and Exchange Commission (the “SEC”) relating to a proposed initial public offering of shares of its Class A common stock.
The number of shares to be offered and the price range for the proposed offering have not yet been determined. Quantinuum intends to list its Class A common stock on the Nasdaq Global Select Market under the ticker symbol “QNT.”
J.P. Morgan and Morgan Stanley (in alphabetical order) are acting as joint lead active book-running managers for the proposed offering. Jefferies and Evercore ISI are also acting as active book-running managers.
The proposed offering is subject to market conditions, and there can be no assurance as to whether or when the offering may be completed, or as to the actual size or terms of the offering.
The proposed offering will be made available only by means of a prospectus. Copies of the preliminary prospectus, when available, may be obtained from: J.P. Morgan Securities LLC, c/o Broadridge Financial Solutions, 1155 Long Island Avenue, Edgewood, NY 11717 or by email at prospectus-eq_fi@jpmchase.com and postsalemanualrequests@broadridge.com; Morgan Stanley & Co. LLC, 180 Varick Street, 2nd Floor, New York, NY 10014, Attention: Prospectus Department or by email at prospectus@morganstanley.com; Jefferies LLC, Attn: Equity Syndicate Prospectus Department, 520 Madison Avenue, New York, New York 10022, by telephone at (877) 821-7388 or by email at Prospectus_Department@Jefferies.com; or Evercore Group L.L.C., Attention: Equity Capital Markets, 55 East 52nd Street, 35th Floor, New York, NY 10055, by telephone at 888-474-0200 or by email at ecm.prospectus@evercore.com.
The registration statement relating to these securities has been filed with the SEC but has not yet become effective. These securities may not be sold, nor may offers to buy be accepted, prior to the time the registration statement becomes effective. This press release shall not constitute an offer to sell or the solicitation of an offer to buy these securities, nor shall there be any sale of these securities in any state or jurisdiction in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such state or jurisdiction. Any offers, solicitations or offers to buy, or any sales of securities will be made in accordance with the registration requirements of the Securities Act of 1933, as amended.
About Honeywell
Honeywell is an integrated operating company serving a broad range of industries and geographies around the world. Our business is aligned with three powerful megatrends – automation, the future of aviation and energy transition – underpinned by our Honeywell Accelerator operating system and Honeywell Forge IoT platform. As a trusted partner, we help organizations solve the world's toughest, most complex challenges, providing actionable solutions and innovations through our Aerospace Technologies, Industrial Automation, Building Automation and Energy and Sustainability Solutions business segments that help make the world smarter, safer, as well as more secure and sustainable. For more news and information on Honeywell, please visit www.honeywell.com/newsroom.
About Quantinuum
Quantinuum is a leading quantum computing company offering a full-stack platform designed to make quantum computing deployable in real-world environments. The company has commercially deployed multiple generations of quantum systems built on the well-established QCCD architecture, which it has implemented with novel designs and capabilities to achieve the industry’s highest accuracy levels based on average two-qubit gate fidelity as of December 31, 2025. Quantinuum has active engagements with market leaders across pharmaceuticals, material science, financial services, and government and industrial markets. Quantinuum’s headquarters is in Broomfield, Colorado, with additional facilities across the United States, United Kingdom, Germany, Japan, and Singapore.
Contacts:
Media
Stacey Jones
(980) 378-6258
Stacey.Jones@honeywell.com
Investor Relations
Mark Macaluso
(704) 627-6118
Mark.Macaluso@honeywell.com
- The companies plan to continue their co-creation partnership to advance future mobility
- BMW to access the latest generations of Quantinuum systems throughout the partnership
- Advanced materials science research supports a range of next-generation technologies
Broomfield, Colorado, May 5th, 2026 — Quantinuum and BMW Group have formally expanded their ongoing collaboration into a multi-year partnership with a mission to unlock future mobility by applying quantum computing toward advanced materials science.
Since 2021, Quantinuum and BMW Group have been collaborating on joint research focused on tackling complex challenges in industrial chemistry to support the advancement of next-generation mobility. The collaboration has progressed from foundational algorithm development to advanced simulations of molecular systems, allowing the researchers to unlock insights into catalytic activity, reaction pathways, and material performance in energy-relevant environments.
The companies have now agreed to extend the work, positioning the alliance to become one of the longest-sustained commitments between a commercial enterprise and a quantum computing provider to date.
“Quantinuum is focused on driving commercial adoption of quantum computing through close collaboration with industry leaders on high-impact applications," said Dr. Rajeeb Hazra, President and CEO of Quantinuum. “Our expanded partnership with the BMW Group underscores this focus, and we’re excited to scale the meaningful work we’ve been advancing together.”
Researchers at BMW Group are utilizing Quantinuum's trapped-ion architecture, which provides the high-fidelity operations necessary to accurately simulate molecular systems, particularly electrochemical processes that play a critical role across a range of technologies relevant to sustainable mobility and the design and optimization of fuel cells.
Under the terms of the agreement, BMW Group will leverage successive generations of Quantinuum’s quantum computers. This includes the current Helios system and upcoming generations, Sol (planned for 2027) and Apollo (planned for 2029). This will enable the teams to validate progress at each stage while scaling toward industrially meaningful solutions.
“We have been exploring quantum computing for many years,” said Dr. Martin Tietze, Vice President of New Technologies at BMW Group. “Together with partners such as Quantinuum, we translate advances in quantum hardware into real‑world applications, including materials optimization, supporting the development of future vehicle generations.”
Quantinuum’s progress toward large-scale, fault-tolerant systems helps to ensure that as the hardware reaches milestones in performance, BMW can apply that computational power to catalyst chemistry research, targeting critical oxygen reduction reaction processes at platinum catalysts to potentially lower costs and improve energy efficiency.
The companies broke new ground in 2024, alongside another commercial partner, as the first to simulate catalytic performance using a quantum computer with results published in Nature Partner Journal.
Beyond its technical achievements, the collaboration has evolved into a deeply connected, cross-disciplinary effort, bringing together quantum scientists, chemists, and engineers in a sustained partnership that reflects both the complexity of the challenge and the scale of the ambition.
About Quantinuum
Quantinuum is a leading quantum computing company offering a full-stack platform designed to make quantum computing deployable in real-world environments. The company has commercially deployed multiple generations of quantum systems built on the well-established QCCD architecture, which it has implemented with novel designs and capabilities to achieve the industry’s highest accuracy levels based on average two-qubit gate fidelity.[i] Quantinuum has active engagements with market leaders across pharmaceuticals, material science, financial services, and government and industrial markets.
The company has a global workforce of approximately 700 employees, including top scientists and researchers. Over 70% of its technology team hold PhDs or Master's degrees. Quantinuum’s headquarters is in Broomfield, Colorado, with additional facilities across the United States, United Kingdom, Germany, Japan, and Singapore.
For more information, please visit www.quantinuum.com.
[i] As of December 31, 2025.