| |
Imec, a world-leading research and innovation hub in nanoelectronics and digital technologies, and Diraq, a pioneer of silicon-based quantum computing, have demonstrated that industrially made silicon quantum dot qubits consistently show error rates that surpass the values needed for quantum error correction. The results, reported in Nature, show that Diraq’s qubits can be manufactured reliably with the tools of the silicon microchip trade, confirming the potential of imec’s industrial manufacturing techniques for developing large-scale silicon-based quantum computers.
Leveraging nearly a decade of careful optimization and engineering of spin-qubit fabrication at imec, Diraq-designed devices were shown to consistently achieve over 99% fidelity in operations involving two quantum bits (or ‘qubits’). This feat, made possible by imec’s advanced spin qubit technology platform, is a crucial step in Diraq’s roadmap toward utility scale the point at which a quantum computer’s value exceeds its cost.
Diraq’s CEO and Founder, Andrew Dzurak, said,“Achieving utility scale in quantum computing hinges on finding a commercially viable way of producing high-fidelity qubits at scale. Diraq’s collaboration with imec makes it clear that silicon-based quantum computers can be built by leveraging the mature semiconductor industry, which opens a cost-effective pathway to chips containing millions of qubits while still maximizing fidelity.”
Technical summary
The fidelity of a quantum operation quantifies how close the actual operation is to its ideal version and is a key metric for enabling large-scale quantum computers. Ideally, fidelities must (far) exceed 99% across all operations. Only then are errors rare enough for quantum error correction methods to work successfully. In this work, fidelities were reproducibly measured for a set of silicon quantum dot spin qubit operations across multiple devices state preparation and measurement of the qubits (SPAM), and one- and two-qubit gate operations performed on the qubits to control their state and entangle them the elementary operations required for a utility-scale quantum computer. Fidelities above 99.9% were achieved for SPAM operations, and fidelities systematically exceeding 99% were shown for one- and two-qubit gate operations, making quantum error correction of industrially fabricated quantum dot qubit devices now a realistic prospect.
Typically, quantum devices fabricated in academic clean rooms are selected for measurement on the basis of their quality, a process that produces ‘hero’ devices, obscuring the reproducibility of the results. In the Nature publication, Diraq measured devices that were selected at random, obtaining reproducible data on sets of two-qubit devices, each consisting of a double quantum-dot structure. The devices were fabricated using imec’s 300mm spin qubit platform for silicon quantum-dot structures, which is optimized for low electrical noise and high uniformity. In order to also suppress the magnetic noise from residual nuclear spins in the substrate, the quantum-dot structures were fabricated on an isotopically enriched 28Si layer.
Kristiaan De Greve, fellow and program director for quantum computing at imec: “For the first time, silicon MOS based quantum-dot spin-qubit devices realized with industrial manufacturing techniques perform as well as academic hero devices. This shows that imec’s 300mm process flow for MOS based quantum-dot structures enables a low-noise qubit environment, resulting in high fidelity values for a set of critical qubit operations. The methods used and insights gained from it also show us that there is further room for fidelity improvement, as higher fidelities can be achieved through even further isotopic enrichment of the silicon-channel layer 28Si"
About imec
Imec (imec-int.com) is a world-leading research and innovation hub in semiconductor technologies. Leveraging its state-of-the-art R&D infrastructure and the expertise of over 6,000 employees, imec drives innovation in semiconductor and system scaling, artificial intelligence, silicon photonics, connectivity, and sensing.
Imec’s advanced research powers breakthroughs across a wide range of industries, including computing, health, automotive, energy, infotainment, industry, agrifood, and security. Through IC-Link, imec guides companies through every step of the chip journey - from initial concept to full-scale manufacturing - delivering customized solutions tailored to meet the most advanced design and production needs.
Imec collaborates with global leaders across the semiconductor value chain, as well as with technology companies, start-ups, academia, and research institutions in Flanders and worldwide. Headquartered in Leuven, Belgium, imec has research facilities across Belgium and in Germany, the Netherlands, Italy, the UK, Spain, and the USA, with representation on three continents. In 2024, imec reported revenues of €1.034 billion.
The imec group holds a global trademark portfolio, including word marks and combined figurative registered and unregistered trademarks, across national, regional, and international territories. Its lawful use requires prior written consent of IMEC in compliance with the IMEC branding guidelines, which may be updated periodically. The latest version is available upon written request.
About Diraq
Diraq (diraq.com) is a global leader in building quantum processors using silicon ‘quantum dot’ technology, leveraging proprietary technology developed over 20 years of research. Diraq is a private company, founded in 2022 and headquartered in Sydney, Australia, with operations in Palo Alto, California, and Boston, Massachusetts. Our approach relies on the existing silicon manufacturing processes, known as CMOS, used by foundries to produce today’s semiconductor components. By capitalizing on existing high-volume chip fabrication technology and semiconductor manufacturing capabilities, Diraq is accelerating the change that can transform computing as we know it. Diraq’s platform architecture is purpose-built to drive the significant processing advances required to reduce cost and energy barriers, and to realize quantum computing’s full societal and economic potential, forging a faster and cheaper road to market. Diraq’s goal is to revolutionize quantum computing by driving qubit numbers on a single chip to the many millions, and ultimately billions needed for useful commercial applications.
|
jade.liu[.]imec.be 
