法人別リリース

IMS Unveils Japan's First Full-stack Neutral-atom Quantum Computer "Shunkai," Now Operational

IMS — Tue, 25 Aug 2026 16:00:00 +0900

OKAZAKI, Japan, Aug. 25, 2026 /Kyodo JBN/ --
Institute for Molecular Science, National Institutes of Natural Sciences
Institute for Molecular Science (hereinafter "IMS"), National Institutes of Natural Sciences, announced on August 24 that Japan's first full-stack neutral-atom quantum computer "Shunkai," developed by a research team led by Professor Kenji Ohmori, is now operational.

Quantum computers are being developed in various modalities worldwide. However, there remain challenges to address for their practical applications, such as scalability and error correction during computation.

Anticipated to overcome those challenges, neutral-atom quantum computing has been rapidly attracting attention from industry, academia and government worldwide as a groundbreaking new modality. Neutral-atom quantum computing uses a single atom as a qubit (*1) and has exceptional features, including:
- Room-temperature operation without the need for a refrigerator.
- Achieve quantum entanglement (*2) (the source of quantum speedup) between arbitrary qubits by moving the atoms (qubits) during computations.
- Flexibly optimize qubit configuration for each algorithm.
- Relatively easy to increase the number of qubits.
- Long lifetime of quantum information in each qubit.

At the IMS, Professor Ohmori is the project manager leading the neutral-atom quantum computing research and development team for the project "Large-scale and high-coherence fault-tolerant quantum computer with dynamical atom arrays" under the Cabinet Office/JST Moonshot Research and Development Program Goal 6, "Realization of a fault-tolerant universal quantum computer." Aiming at practical quantum computers, the team has developed Japan's first full-stack neutral-atom quantum computer named Shunkai (see Fig. 1).

A "full-stack" system, as shown in Fig. 2, refers to a system that integrates multiple layers (stacks) necessary for converting user inputs into drive signals for the computing device to execute computational output as its result. Personal computers and supercomputers are examples of full-stack systems. Inside Shunkai, atomic qubits are captured in an array using "optical tweezers (*3)" generated by tightly focusing laser light with an objective lens. Quantum calculations are performed by irradiating the atoms with microwaves or laser light. The computational results are interpreted by observing the fluorescence from each individual atom with a camera. The IMS has taken the lead in developing this full-stack quantum computer, leveraging a strong industry-academia collaboration within the Ohmori Moonshot Project with Hitachi, Ltd. for the software stack and with Infleqtion, Inc. for the Quantum Processing Unit (QPU) stack.

Shunkai will use approximately 50 qubits in its early stage, and will expand its scale to approximately 500 qubits. The system will be partially open to external users for the development of its applications and the demonstration and improvement of quantum error correction (*4). Plans also include collaboration with Yaqumo Inc., where Professor Ohmori serves as a founder and executive advisor, from the viewpoint of the social implementation and upgrade of the quantum computer.

Future Developments
In the second stage of the Ohmori Moonshot Project "Neutral atom-based fault-tolerant quantum computer" that just started in April 2026, the team will operate this full-stack quantum computer to further develop and improve the integration and control technologies, upgrade the system toward fault tolerance and larger scales, and enable high stability and high-fidelity quantum computation for extended periods of time. By March 2031, at the end of the second stage, the goal is to realize a large-scale, high-performance neutral-atom fault-tolerant quantum computer, with 10,000 physical qubits and quantum error detection and correction capabilities, available to external users.

Message from Professor Kenji Ohmori, Institute for Molecular Science:
"Neutral atom-based quantum computers have recently been rapidly attracting attention around the world as a new modality that could exceed the limits of the superconducting modality, which started its development earlier. I think it is extremely significant that now we have developed Japan's first full-stack quantum computer in this cutting-edge modality and started its operation. We expect that the external use of our full-stack machine Shunkai, for example, by the theory and software researchers for the development of error-correction technologies, and by the corporate researchers toward practical applications would lead to ripple effects on various fields in industry, academia and government around the world. It is also expected that Shunkai will be integrated with the existing shared supercomputer facility at the IMS to develop into a quantum-GPU hybrid computing center."

About Shunkai
It is named after Harumi Shibukawa, where his given name "Harumi" is also pronounced as Shunkai, an Edo-period (1603-1867) astronomer who established the first original calendar system in Japan. Calculations of celestial motion on the celestial sphere evoke the precise control of quantum states on the "Bloch sphere," which represents the state of a qubit in the physics expert community. With the highest respect to Shibukawa who developed Japan's first indigenous calendar based on precise calculations, this system Shunkai has been named in the hope that Japan's first full-stack neutral-atom quantum computer will perform precise quantum computations.
(Takafumi Tomita, Assistant Professor, Institute for Molecular Science, National Institutes of Natural Sciences)

Glossary
(*1) Qubit: The basic unit of information in a quantum computer. Unlike conventional bits, which can only take on either "0" or "1," a quantum bit can simultaneously represent both "0" and "1" states through quantum mechanical "superposition."

(*2) Quantum entanglement: A phenomenon unique to quantum mechanics where two or more particles (quanta) maintain a strong correlation with each other, even at distances, and the observation result of one instantly determines the state of the other.

(*3) Optical tweezer: A technique that uses laser light to capture particles such as atoms or dielectric particles near the focal point.

(*4) Quantum error correction: A technique for correcting calculation errors caused by the imperfection of manipulations and influence of the surrounding environment on quantum bits during the calculation process. Because quantum states are extremely fragile and easily broken, this technique is essential for quantum computers.

Research funding: https://kyodonewsprwire.jp/attach/202604237994-O11-DaDJ5C71.pdf
Photo/Figure: https://kyodonewsprwire.jp/attach/202604237994-O10-e1L56Rhq.pdf
Related links: https://kyodonewsprwire.jp/attach/202604237994-O9-QN8TFY9J.pdf

IMS Developing Japan's First "Cold (Neutral) Atom" Quantum Computers: New Collaboration with ...

IMS — Tue, 12 Mar 2024 15:00:00 +0900

OKAZAKI, Japan, Mar. 12, 2024 /Kyodo JBN/ --
Institute for Molecular Science, National Institutes of Natural Sciences
IMS Developing Japan's First "Cold (Neutral) Atom" Quantum Computers: New Collaboration with 10 Industry Partners toward Commercialization

Institute for Molecular Science (hereinafter "the IMS"), National Institutes of Natural Sciences, has established a "Commercialization Preparatory Platform (PF)" to accelerate the development of novel quantum computers, based on the achievement of a research group led by Prof. Kenji Ohmori. The launch of the PF was made possible by collaboration with 10 industry partners, including companies and financial institutions.

The 10 partners that joined the PF include (listed alphabetically): blueqat Inc., Development Bank of Japan Inc., Fujitsu Limited, Groovenauts, Inc., Hamamatsu Photonics K.K., Hitachi, Ltd., and NEC Corporation.

With the PF in place, the IMS will leverage the expertise of the participating companies and seek for advice and support on matters related to commercialization, such as the processes of establishing a start-up company, developing domestically produced quantum computers, and R&D efforts to enable practical application of quantum computers and their associated services. It plans to launch a start-up company by the end of its FY2024 and begin the development of "cold (neutral) atom" quantum computers.

Background
Fierce competition is underway globally for the development of quantum computers by various modalities. However, there remain a number of issues that need to be addressed in order to ensure that these computers can be used practically; these issues include the need to expand the scale of these computers and the ability to take measures against errors that may occur during computation. In recent years, the "cold (neutral) atom" modality, which uses individual atoms as qubits, has been attracting attention from industry, academia, and governments around the world as a revolutionary new method to overcome these issues. Another feature of the cold (neutral) atom modality is that it operates at room temperature and does not require any refrigerators, which are necessary for the superconducting qubit and silicon qubit modalities.

The Ohmori group at the IMS is leading the world in developing the cold (neutral) atom quantum computers. The group has a number of technological advantages and core competencies (*1), including "optical tweezers" and microscope technologies to control a large number of high-quality qubits on a flat surface, and "ultrafast two-qubit gates" that use an ultrafast laser to create a quantum entanglement between two qubits in just 6.5 nanoseconds. In particular, the two-qubit gates represent an important core technology that enables the extraordinary computational speed of quantum computers. In 2022, the ultrafast two-qubit gates developed by the Ohmori group achieved a disruptive innovation that accelerates the two-qubit gates of the conventional cold (neutral) atom method by two orders of magnitude at once.

By taking advantage of these technical advances and core competencies of the Ohmori group, the IMS will accelerate the development and commercialization of quantum computers in collaboration with its industry partners.

World's first demonstration of quantum supremacy using superconducting quantum computers in 2019 (*2)
Message from Professor John Martinis, University of California, Santa Barbara:
"Professor Kenji Ohmori and his team have recently made a major breakthrough to overcome the weakness of the neutral atom method by using ultrafast lasers to drastically accelerate its two-qubit gate by two orders of magnitude. Their optical tweezers and microscope technology for manipulating individual atomic qubits is also outstanding. The team is therefore an extremely promising candidate for the realization of a practical quantum computer in the near future. I would like to actively participate in and contribute to the practical application and commercialization of their quantum computer by making use of my experience."

Message from Yuki Takemori, General Manager, Innovation Promotion Office, Business Planning & Coordination Department, Development Bank of Japan Inc.
Project General Manager of PF:
"After the bursting of the bubble economy, the Japanese economy spent the 'lost 30 years' without a clue to its further growth. I expect that quantum computing will be a technology that will bring revolutionary evolution to mankind, similar to the Internet and artificial intelligence (AI). It will grow into an extremely important industry for Japan, acting as a catalyst for its development and advancement. The technological capabilities of Professor Kenji Ohmori and his team are a global treasure and a trump card for the revival of the Japanese economy. I expect that this project will spread its wings far and wide."

Message from Professor Kenji Ohmori, Institute for Molecular Science:
"I would like to express my sincere gratitude for the support of such distinguished companies for the development of our cold-atom (neutral-atom) quantum computer. Although we have absolute confidence in our basic technology, the development of practical quantum computers requires the integration of a variety of 'enabling technologies' including conventional electronics, software, system engineering, and architecture. With the launch of this commercialization platform, we will further strengthen our development efforts and work hard to create a quantum computer that can contribute to our society as soon as possible."

Notes:
(*1) Core competency: a defining capability that distinguishes an enterprise from its competitors
(*2) Quantum supremacy: a demonstration of a quantum computer's advantage over classical computers, including supercomputers, to process calculations that would conventionally take a long time to process at unmatched speeds

For more information, please visit:
Research funding: https://kyodonewsprwire.jp/attach/202403077687-O2-hlc67mcx.pdf
Photo/Figure: https://kyodonewsprwire.jp/attach/202403077687-O1-coSasezF.pdf
Related links: https://kyodonewsprwire.jp/attach/202403077687-O3-9KCZgK5F.pdf