IBM and RIKEN, a national research laboratory in Japan, have unveiled the first IBM Quantum System Two ever to be deployed outside of the United States and beyond an IBM Quantum Data Center.
The availability of this system also marks a milestone as the first quantum computer to be co-located with RIKEN’s supercomputer Fugaku — one of the most powerful classical systems on Earth. This effort is supported by the New Energy and Industrial Technology Development Organization (NEDO), an organization under the jurisdiction of Japan’s Ministry of Economy, Trade and Industry (METI)’s “Development of Integrated Utilization Technology for Quantum and Supercomputers” as part of the “Project for Research and Development of Enhanced Infrastructures for Post 5G Information and Communications Systems.”
IBM Quantum System Two at RIKEN is powered by IBM’s 156-qubit IBM Quantum Heron, the company’s best performing quantum processor to-date. IBM Heron’s quality as measured by the two-qubit error rate, across a 100-qubit layered circuit, is 3×10-3 (with the best two-qubit error being 1×10-3) — which is 10 times better than the previous generation 127-qubit IBM Quantum Eagle. IBM Heron’s speed, as measured by the CLOPS (circuit layer operations per second) metric is 250,000, which reflects another 10x improvement in the past year, over IBM Eagle.
At a scale of 156 qubits, with these quality and speed metrics, Heron is the most performant quantum processor in the world. This latest Heron is capable of running quantum circuits that are beyond brute-force simulations on classical computers, and its connection to Fugaku will enable RIKEN teams to use quantum-centric supercomputing approaches to push forward research on advanced algorithms, such as fundamental chemistry problems.
The new IBM Quantum System Two is co-located with Fugaku within the RIKEN Center for Computational Science (R-CCS), Japan’s premier high-performance computing (HPC) center. The computers are linked through a high-speed network at the fundamental instruction level to form a proving ground for quantum-centric supercomputing.
This low-level integration allows RIKEN and IBM engineers to develop parallelized workloads, low-latency classical-quantum communication protocols, and advanced compilation passes and libraries. Because quantum and classical systems will ultimately offer different computational strengths, this will allow each paradigm to seamlessly perform the parts of an algorithm for which it is best suited.
This quantum computer expands IBM’s global fleet of quantum computers, and was officially launched during a ribbon-cutting ceremony on June 24, 2025, in Kobe, Japan. The event featured opening remarks from RIKEN President, Makoto Gonokami; Jay Gambetta, IBM Fellow and VP of IBM Quantum; Akio Yamaguchi, GM of IBM Japan; as well as local parliament members and representatives from the Kobe Prefecture and City, METI, NEDO, and MEXT.
“The future of computing is quantum-centric and with our partners at RIKEN we are taking a big step forward to make this vision a reality,” said Jay Gambetta, IBM Quantum. “The new IBM Quantum System Two powered by our latest Heron processor and connected to Fugaku, will allow scientists and engineers to push the limits of what is possible.”
“By combining Fugaku and the IBM Quantum System Two, RIKEN aims to lead Japan into a new era of high-performance computing,” said Dr. Mitsuhisa Sato, Division Director of the Quantum-HPC Hybrid Platform Division, RIKEN Center for Computational Science. “Our mission is to develop and demonstrate practical quantum-HPC hybrid workflows that can be explored by both the scientific community and industry. The connection of these two systems enables us to take critical steps toward realizing this vision.”
The installation of IBM Quantum System Two at RIKEN is poised to expand previous achievements by RIKEN and IBM researchers as they seek to discover algorithms that offer quantum advantage: the point at which a quantum computer can solve a problem faster, cheaper, or more accurately than any known classical method.
This includes work recently featured on the cover of Science Advances, based on sample-based quantum diagonalization (SQD) techniques to accurately model the electronic structure of iron sulfides, a compound present widely in nature and organic systems.
The ability to realistically model such a complex system is essential for many problems in chemistry, and was historically believed to require fault-tolerant quantum computers. SQD workflows are among the first demonstrations of how the near-term quantum computers of today can provide scientific value when integrated with powerful classical infrastructure.