Fujitsu Limited and RIKEN have developed a cutting-edge 256-qubit superconducting quantum computer at the RIKEN RQC-FUJITSU Collaboration Center, building on the 64-qubit version launched in October 2023 with support from Japan’s Ministry of Education, Culture, Sports, Science and Technology (MEXT). This advancement incorporates high-density implementation techniques, marking a significant step toward practical applications of superconducting quantum computers to address complex global issues. Starting in the first quarter of fiscal 2025, the 256-qubit quantum computer will be integrated into a hybrid quantum computing platform and offered to companies and research institutions worldwide, enabling more complex analyses and sophisticated error correction algorithms.
Moving forward, both organizations will further enhance the platform’s usability by working to enable seamless collaboration between quantum and classical computers, enabling the efficient execution of hybrid quantum-classical algorithms.
Fujitsu and RIKEN’s 256-qubit superconducting quantum computer overcomes some key technical challenges, including appropriate cooling within the dilution refrigerator which is achieved through the incorporation of high-density implementation and cutting-edge thermal design. Other key features include:
1. Scalable 3D connection structure
- Enables efficient scaling of qubit count without requiring complex redesigns by arranging 4-qubit unit cells in a 3D configuration
- The 256-qubit machine utilizes the same unit cell design established in its 64-qubit predecessor, effectively demonstrating the scalability of this architectural approach
2. Quadrupled implementation density within dilution refrigerator
- Quadrupled implementation density achieved within the dilution refrigerator, allowing the 256-qubit machine to operate within the same cooling unit as the 64-qubit system
- Highly optimized design that carefully balances heat generation from control circuits with the cooling capacity of the refrigerator, while maintaining the necessary ultra-high vacuum and extremely low temperatures
Fujitsu is committed to accelerating the practical application of quantum computers from both hardware and software perspectives. Through its platform for hybrid quantum computing, Fujitsu will provide larger-scale quantum computers to global companies and research institutions conducting joint research in various fields, including finance and drug discovery.
Fujitsu and RIKEN will continue R&D efforts toward the launch of a 1,000-qubit computer, which is scheduled to be installed in a new building at Fujitsu Technology Park in 2026. In addition, the two organizations will extend the installation period of their Collaboration Center from March 2025 to March 2029, and will continue to work on the long-term R&D of technologies that will enable the realization of even larger superconducting quantum computers.
For more information: Fujitsu
Image: Newly developed 256-qubit superconducting quantum computer
