Japan now has a quantum computer that can take a job, run it and return a result. Quantum computers are being developed for problems that can be difficult for conventional computers to solve efficiently, including some optimisation, simulation and materials-science problems.

IMS says Shunkai will be partially open to external users, but it has not disclosed how an external organisation can apply for access or on what terms.

Shunkai is working scientific infrastructure. An accessible customer market would need something more: disclosed rules for applying, allocating capacity, pricing and service.

What happened

On 24 August 2026, the Institute for Molecular Science (IMS), part of Japan's National Institutes of Natural Sciences, said Shunkai was operational. The institute described it as Japan's first full-stack neutral-atom quantum computer, developed by a team led by Professor Kenji Ohmori.

“Full-stack” matters because IMS isn't describing a component or processor alone. The system takes a user's input, controls atoms held in optical tweezers, manipulates them with light and reads the result through a camera. Hitachi supplied software, Infleqtion supplied the quantum-processing stack and IMS integrated the system.

Shunkai starts at approximately 50 qubits, with a planned path to approximately 500. IMS also cites a Moonshot programme goal of 10,000 physical qubits by March 2031, with error detection and correction. That larger figure describes the programme's destination rather than capacity deployed today.

Access is narrower than the word operational may suggest to a business reader. IMS says Shunkai will be “partially open to external users” for application development and work on quantum error correction. Ohmori identified theory and software researchers, as well as corporate researchers working towards practical applications, as potential users.

The programme milestones also point to staged research participation. Japan Science and Technology Agency (JST) milestones place external users within the Ohmori project in 2028 and users outside it in 2030. These are future milestones; they do not explain how IMS's partial opening will work now or establish a general commercial service.

Elsewhere in APAC, the machines are at different stages: Quantinuum's H2 was being assembled at RIKEN in April; Helios remained planned for Singapore in March; and IonQ's Tempo was being installed in South Korea in September, with service targeted for April 2027.

What it means

Operational describes the state of the machine. Shunkai's hardware and software can take an instruction through the physical process and produce an output. Japan has therefore crossed a real engineering threshold beyond a procurement plan or a future deployment.

A market requires an access mechanism around that capability. An organisation needs to know who may submit work, how scarce capacity is assigned, what access costs, what result it receives and what service commitment applies. The supplied record sets out research purposes and programme milestones, but gives no public price, allocation rules or booking route.

That boundary does not diminish the investment. Moonshot funding, IMS integration and contributions from Hitachi and Infleqtion are building knowledge, equipment and operating experience. Public research infrastructure often comes before a service that companies can buy.

But it changes what the August announcement can prove. The switch-on establishes that Japan can operate the full stack. It does not establish customer demand, commercial access or the terms on which an organisation can obtain compute.

Shunkai has crossed the engineering threshold from planned system to working machine. The next threshold is access: turning partial research access into something an organisation can obtain on disclosed terms.

What to watch

• First external run. Whether IMS identifies a user outside the Ohmori project, what work they submit and what result they obtain.

• Terms of access. Whether IMS publishes an application route, allocation rules, pricing or a service commitment as the 2028 and 2030 programme milestones approach.

• Regional services. Whether Helios in Singapore and Tempo in South Korea move from deployment plans into disclosed services that researchers or companies can actually access.