#quantumheronprocessor

IBM quantum centric supercomputing

IBM and RIKEN researchers used the Fugaku supercomputer and a quantum processor to solve complex chemical equations. This cooperation's closed-loop methodology allowed the two systems to work together and share data continuously. Using a hybrid method, the scientists mapped iron-sulfur compound electrical structures with unprecedented precision. This milestone enables real scientific applications by showing that quantum-centric supercomputing can scale. The work shows a shift toward seamless quantum-classical coordination to enhance computational power and efficiency.

Quantum-centric supercomputer chemistry beyond exact solutions

RIKEN and IBM demonstrated quantum-centric supercomputing (QCSC) at a scale never before feasible, advancing HPC. In a collaborative research initiative, the teams coordinated the Fugaku supercomputer, one of the world's most powerful classical systems, with an IBM Quantum Heron processor on-site. This partnership accomplished the largest and most exact quantum chemistry experiment on a quantum computer, marking a turning point in quantum advantage research.

IBM Director of Research Jay Gambetta presented the experiment at Supercomputing Asia 2026 on January 29. It sought to determine two iron-sulfur molecules' complex electrical structure. Since electron distribution and behavior impact a molecule's interactions and reactions with its surroundings, understanding these structures is a basic chemistry challenge. A very exact answer by the study team revealed that quantum and classical resources can be combined in a smooth, “closed-loop” execution to solve issues that are too tough for precise classical procedures.

An Innovative Method: “Closed-Loop” Workflow

This requires creating and executing a closed-loop workflow. This experiment fed data back and forth in an uninterrupted, iterative cycle, unlike conventional hybrid setups, where a quantum processing unit (QPU) finishes a task before sending results back for classical processing. Practical quantum computing in HPC, where real-world applications require close integration of various compute kinds, is more like this orchestration.

Given its enormity, the orchestration is technically complex. Researchers had to build a complicated job assignment method to use the Fugaku supercomputer and Heron processor during computing. Any idle time wastes valuable runtime for other investigations since classical and quantum resources are expensive and valuable. As a billion-dollar machine, Fugaku must maximize its uptime and avoid “sitting around” during quantum steps. The new approach lowered “time-to-solution” by running both computers as near to simultaneously as possible.

SQD: Hybrid Algorithm Power

The discovery was based on hybrid quantum-classical algorithms sample-based quantum diagonalization (SQD). These algorithms divide a problem into conventional and quantum components. The quantum computer unlatches the hardest aspect of the problem, allowing the classical supercomputer to “turn the handle and open the door,” like the “lifting pin in a lockpicking set,” according to the researchers.

Electronic structure simulations have a vast number of electron combinations that grows exponentially with molecular complexity. This vast region was sampled using the IBM Quantum Heron processor in the SQD workflow to identify traditional computer focus areas. With this understanding, Fugaku reached a conclusion. The systems achieved results similar to state-of-the-art classical approximation techniques and far more accurate than quantum approaches when working together.

Heron-Fugaku Hardware Cooperation

This milestone's hardware is cutting-edge conventional and quantum technology. The 2020–2021 world's fastest computer, Fugaku, provided the experiment's classical foundation. The huge device has 158,976 48-core chips. The system revealed future quantum-centric supercomputing architecture when paired with RIKEN's IBM Quantum Heron CPU.

Director of the Quantum-HPC Hybrid Platform Division at the RIKEN Center for Computational Science, Mitsuhisa Sato, called the achievement “very exciting development for hybrid computing”. The process was designed for Fugaku's architecture, but the researchers found it could be utilized in other cloud-based HPC setups. This shows that standard HPC infrastructures worldwide can interface with quantum computers.

Toward future

Despite this success, the route to full-scale quantum advantage continues. The RIKEN-IBM team expects to integrate GPUs as accelerators into quantum-classical processes next. GPUs using hybrid algorithms like SQD may speed up the process, according to recent studies.