Announcing Quixer – Quantinuum’s State-of-the-Art Quantum Transformer, Making Quantum AI a Little More Realistic

July 13, 2024

The marriage of AI and quantum computing holds big promise: the computational power of quantum computers could lead to huge breakthroughs in this next-gen tech. A team led by Stephen Clark, our Head of AI, has just helped us move towards unlocking this incredible potential.

A key ingredient in contemporary classical AI is the “transformer”, which is so important it is actually the “T” in ChatGPT. Transformers are machine learning models that do things like predict the next word in a sentence, or determine if a movie review is positive or negative. Transformers are incredibly well-suited to classical computers, taking advantage of the massive parallelism afforded by GPUs. These advantages are not necessarily present on quantum computers in the same way, so successfully implementing a transformer on quantum hardware is no easy task.

Until recently, most attempts to implement transformers on quantum computers took a sort of “copy-paste” approach – taking the math from a classical implementation and directly implementing it on quantum circuits. This “copy-paste” approach fails to account for the considerable differences between quantum and classical architectures, leading to inefficiencies. In fact, they are not really taking advantage of the ‘quantum’ paradigm at all.

This has now changed. In a new paper on the arXiv, our team introduces an explicitly quantum transformer, which they call “Quixer” (short for quantum mixer). Using quantum algorithmic primitives, the team created a transformer implementation that is specially tailored for quantum circuits, making it qubit efficient and providing the potential to offer speedups over classical implementations.

Critically, the team then applied it to a practical language modelling task (by simulating the process on a classical computer), obtaining results that are competitive with an equivalent classical baseline. This is an incredible milestone achievement in and of itself.

This paper also marks the first quantum machine learning model applied to language on a realistic rather than toy dataset. This is a truly exciting advance for anyone interested in the union of quantum computing and artificial intelligence. About a week ago when we announced that our System Model H2 has bested the quantum supremacy experiments first benchmarked by Google, we promised a summer of important advances in quantum computing. Stay tuned for more disclosures!

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. 

Blog
June 10, 2025
Our Hardware is Now Running Quantum Transformers!

If we are to create ‘next-gen’ AI that takes full advantage of the power of quantum computers, we need to start with quantum native transformers. Today we announce yet again that Quantinuum continues to lead by demonstrating concrete progress — advancing from theoretical models to real quantum deployment.

The future of AI won't be built on yesterday’s tech. If we're serious about creating next-generation AI that unlocks the full promise of quantum computing, then we must build quantum-native models—designed for quantum, from the ground up.

Around this time last year, we introduced Quixer, a state-of-the-art quantum-native transformer. Today, we’re thrilled to announce a major milestone: one year on, Quixer is now running natively on quantum hardware.

Why this matters: Quantum AI, born native

This marks a turning point for the industry: realizing quantum-native AI opens a world of possibilities.

Classical transformers revolutionized AI. They power everything from ChatGPT to real-time translation, computer vision, drug discovery, and algorithmic trading. Now, Quixer sets the stage for a similar leap — but for quantum-native computation. Because quantum computers differ fundamentally from classical computers, we expect a whole new host of valuable applications to emerge.  

Achieving that future requires models that are efficient, scalable, and actually run on today’s quantum hardware.

That’s what we’ve built.

What makes Quixer different?

Until Quixer, quantum transformers were the result of a brute force “copy-paste” approach: taking the math from a classical model and putting it onto a quantum circuit. However, this approach does not account for the considerable differences between quantum and classical architectures, leading to substantial resource requirements.

Quixer is different: it’s not a translation – it's an innovation.

With Quixer, our team introduced an explicitly quantum transformer, built from the ground up using quantum algorithmic primitives. Because Quixer is tailored for quantum circuits, it's more resource efficient than most competing approaches.

As quantum computing advances toward fault tolerance, Quixer is built to scale with it.

What’s next for Quixer?

We’ve already deployed Quixer on real-world data: genomic sequence analysis, a high-impact classification task in biotech. We're happy to report that its performance is already approaching that of classical models, even in this first implementation.

This is just the beginning.

Looking ahead, we’ll explore using Quixer anywhere classical transformers have proven to be useful; such as language modeling, image classification, quantum chemistry, and beyond. More excitingly, we expect use cases to emerge that are quantum-specific, impossible on classical hardware.

This milestone isn’t just about one model. It’s a signal that the quantum AI era has begun, and that Quantinuum is leading the charge with real results, not empty hype.

Stay tuned. The revolution is only getting started.

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Blog
June 9, 2025
Join us at ISC25

Our team is participating in ISC High Performance 2025 (ISC 2025) from June 10-13 in Hamburg, Germany!

As quantum computing accelerates, so does the urgency to integrate its capabilities into today’s high-performance computing (HPC) and AI environments. At ISC 2025, meet the Quantinuum team to learn how the highest performing quantum systems on the market, combined with advanced software and powerful collaborations, are helping organizations take the next step in their compute strategy.

Quantinuum is leading the industry across every major vector: performance, hybrid integration, scientific innovation, global collaboration and ease of access.

  • Our industry-leading quantum computer holds the record for performance with a Quantum Volume of 2²³ = 8,388,608 and the highest fidelity on a commercially available QPU available to our users every time they access our systems.
  • Our systems have been validated by a #1 ranking against competitors in a recent benchmarking study by Jülich Research Centre.
  • We’ve laid out a clear roadmap to reach universal, fully fault-tolerant quantum computing by the end of the decade and will launch our next-generation system, Helios, later this year.
  • We are advancing real-world hybrid compute with partners such as RIKEN, NVIDIA, SoftBank, STFC Hartree Center and are pioneering applications such as our own GenQAI framework.
Exhibit Hall

From June 10–13, in Hamburg, Germany, visit us at Booth B40 in the Exhibition Hall or attend one of our technical talks to explore how our quantum technologies are pushing the boundaries of what’s possible across HPC.

Presentations & Demos

Throughout ISC, our team will present on the most important topics in HPC and quantum computing integration—from near-term hybrid use cases to hardware innovations and future roadmaps.

Multicore World Networking Event

  • Monday, June 9 | 7:00pm – 9:00 PM at Hofbräu Wirtshaus Esplanade
    In partnership with Multicore World, join us for a Quantinuum-sponsored Happy Hour to explore the present and future of quantum computing with Quantinuum CCO, Dr. Nash Palaniswamy, and network with our team.
    Register here

H1 x CUDA-Q Demonstration

  • All Week at Booth B40
    We’re showcasing a live demonstration of NVIDIA’s CUDA-Q platform running on Quantinuum’s industry-leading quantum hardware. This new integration paves the way for hybrid compute solutions in optimization, AI, and chemistry.
    Register for a demo

HPC Solutions Forum

  • Wednesday, June 11 | 2:20 – 2:40 PM
    “Enabling Scientific Discovery with Generative Quantum AI” – Presented by Maud Einhorn, Technical Account Executive at Quantinuum, discover how hybrid quantum-classical workflows are powering novel use cases in scientific discovery.
See You There!

Whether you're exploring hybrid solutions today or planning for large-scale quantum deployment tomorrow, ISC 2025 is the place to begin the conversation.

We look forward to seeing you in Hamburg!

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Blog
May 27, 2025
Teleporting to new heights

Quantinuum has once again raised the bar—setting a record in teleportation, and advancing our leadership in the race toward universal fault-tolerant quantum computing.

Last year, we published a paper in Science demonstrating the first-ever fault-tolerant teleportation of a logical qubit. At the time, we outlined how crucial teleportation is to realize large-scale fault tolerant quantum computers. Given the high degree of system performance and capabilities required to run the protocol (e.g., multiple qubits, high-fidelity state-preparation, entangling operations, mid-circuit measurement, etc.), teleportation is recognized as an excellent measure of system maturity.

Today we’re building on last year’s breakthrough, having recently achieved a record logical teleportation fidelity of 99.82% – up from 97.5% in last year’s result. What’s more, our logical qubit teleportation fidelity now exceeds our physical qubit teleportation fidelity, passing the break-even point that establishes our H2 system as the gold standard for complex quantum operations.

Figure 1: Fidelity of two-bit state teleportation for physical qubit experiments and logical qubit experiments using the d=3 color code (Steane code). The same QASM programs that were ran during March 2024 on the Quantinuum's H2-1 device were reran on the same device on April to March 2025. Thanks to the improvements made to H2-1 from 2024 to 2025, physical error rates have been reduced leading to increased fidelity for both the physical and logical level teleportation experiments. The results imply a logical error rate that is 2.3 times smaller than the physical error rate while being statistically well separated, thus indicating the logical fidelities are below break-even for teleportation.

This progress reflects the strength and flexibility of our Quantum Charge Coupled Device (QCCD) architecture. The native high fidelity of our QCCD architecture enables us to perform highly complex demonstrations like this that nobody else has yet to match. Further, our ability to perform conditional logic and real-time decoding was crucial for implementing the Steane error correction code used in this work, and our all-to-all connectivity was essential for performing the high-fidelity transversal gates that drove the protocol.

Teleportation schemes like this allow us to “trade space for time,” meaning that we can do quantum error correction more quickly, reducing our time to solution. Additionally, teleportation enables long-range communication during logical computation, which translates to higher connectivity in logical algorithms, improving computational power.

This demonstration underscores our ongoing commitment to reducing logical error rates, which is critical for realizing the promise of quantum computing. Quantinuum continues to lead in quantum hardware performance, algorithms, and error correction—and we’ll extend our leadership come the launch of our next generation system, Helios, in just a matter of months.

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