Hello, I'm Takita from the Quantum Research Institute. Since joining the company, I have engaged in research and development across various fields, starting with optical communication systems and networks, then moving on to general networking, edge computing, and optimization (quantum-inspired optimization). Starting in fiscal year 2024, I became involved with quantum computing and am currently working on creating applications for it.
Introduction
Fujitsu Limited is a leading company proceeding research and development in quantum computing. In April 2025, it issued a press release regarding the development of a world-leading 256-qubit superconducting quantum computer[1]. Furthermore, in August 2025, it announced its goal to develop a superconducting quantum computer exceeding 10,000 physical qubits by 2030[2]. Therefore, to promote Fujitsu's quantum computer and our envisioned quantum computing applications, we exhibited at SC25, the premier computing conference. Figure 1 shows a photo of our booth showcasing the quantum computer and its applications.
(NOTE: This article was generated using machine translation.)
About SC2025
SC is an annual international conference and exhibition on cutting-edge HPC (High Performance Computing) technologies held in the United States each November. This year's event took place at the America's Center in St. Louis, attracting over 16,500 attendees and featuring a record-breaking 559 exhibits, making it a tremendous success [3]. Major computing companies like Intel, Microsoft, Dell, and AWS all had exhibits, and the presence of Japanese companies and universities was also impressive. Quantum computer-related presentations and exhibits still seem to be a minority of the overall offerings, but I expect them to increase going forward. I also attended technical sessions between exhibits. There were more sessions on quantum computers than I had anticipated. However, it was often stated that quantum computers are not intended to directly replace existing CPUs, but rather function as accelerators within supercomputer systems. Therefore, computing will involve using QPUs (Quantum Processing Units) alongside CPUs and GPUs, each in their appropriate roles. However, quantum computing resources are still limited, and obtaining results takes time. Discussions at the workshop included topics like how to schedule QPUs alongside other computational resources.
About Quantum Computers
The highlight of the demo was undoubtedly the actual half-scale mockup of a quantum computer shown in Figure 1, which proved extremely popular once again. Most attendees seemed to arrive with a "What exactly is a quantum computer?" attitude. So, starting with "This ultra-luxurious chandelier is a quantum computer!" as an explanation was a great icebreaker. Indeed, the metal parts are gold-plated, and combined with the lighting from below, it creates a truly gorgeous appearance. Of course, the design of this quantum computer has specific reasons. The entire structure is gold-plated to prevent metal oxidation. Furthermore, every component, even the placement of amplifiers, is meticulously designed to maximize energy efficiency while cooling the quantum computer chips to near absolute zero. The specific image and effects of this are shown in Figure 2. Explaining these details at the venue seemed to leave visitors very satisfied.
Meanwhile, in Japan, it's becoming fairly well known that Fujitsu is seriously engaged in quantum computer research and development, but its international recognition is still limited. In fact, many foreign visitors to our booth were unaware that Fujitsu builds quantum computers. Therefore, this event provided a valuable opportunity to highlight that Fujitsu is indeed developing quantum computers!
What Are Quantum Computer Applications?
Quantum computers are anticipated as revolutionary new computational resources. To take it a step further and spark interest in the question, "What can quantum computers actually be used for?", we also prepared exhibits showcasing specific applications considered achievable with quantum computers. Figure 3 explains Fujitsu's approach to realizing applications using quantum computers. We firmly believe quantum computing holds the potential to profoundly transform society in the future. However, we recognize that quantum computers alone cannot solve the diverse problems facing the world. Therefore, we consider it useful to combine our strengths—technologies already in practical use like "AI," "optimization techniques," and "supercomputers"—while maximizing the "quantum advantage."
As one concrete example, we exhibited a catalyst search application developed through joint research with Professor Yasushi Sekine's group at Waseda University. We will briefly explain this content below. A catalyst is a substance that accelerates chemical reactions or causes only specific reactions to occur. For example, as shown in the diagram at the top of Figure 4, it is also used to decompose harmful carbon monoxide into harmless carbon dioxide and hydrogen.
Since such reactions occur on the surface of materials, developing new catalysts requires an accurate understanding of the surface structures these materials can form. The first step (Step 1) involves a process of comprehensively exploring all possible surface structures a crystal can adopt. Surface structure refers to the cross-section of a material, as shown in this 3D model. However, even slight changes in the cutting direction or location can drastically alter the appearance of the cross-section, resulting in an enormous number of possible patterns. In catalyst research, understanding these cut surfaces is crucial. However, extracting this vast array of patterns has been quite difficult with conventional technology. Through collaborative research, we have demonstrated the principle that using quantum algorithms can comprehensively and efficiently search for complex catalyst surface structures, as shown here [4].Figure 5 shows an image of the demo software for this step. It suggests that once quantum computers are available and this mechanism can be utilized, it will become possible to easily calculate and extract various surface structures, even for large molecules.
Next, simulations are performed to determine how adsorption occurs on each surface structure identified through the above quantum computing procedure [5]. Figure 6 illustrates this concrete concept, showing that numerous adsorption simulation results under various conditions have been obtained for each surface derived in Step 1.
If this series of computational workflows can be realized, it will enable us to replace most of the processes that previously required significant time and cost with computer simulations instead of experiments. This will allow us to collect vast amounts of experimental data. We are now actively considering whether, by training AI on this data, we could infer new catalyst structures. We are continuing to explore this direction. We presented this concept for a future catalyst exploration application at the exhibition. Some attendees remarked that it was impressive not just because quantum chemistry enables the calculations, but because we could propose such a concrete application. We believe this made for a meaningful exhibition.
Conclusion
This was my first time participating in an international computing conference as an exhibitor showcasing quantum computing. Within the computing field, quantum computers are anticipated as accelerators for computation in certain applications. However, we are not yet at a stage where we can definitively state what specific applications they can be used for. The focus is currently on the preliminary stage of demonstrating how supercomputers and quantum computers can be integrated into a usable system. Achieving this would then lead to the next phase: proving whether proposals like the one we presented actually work. However, this will require steady, ongoing research and development.
However, I could clearly sense the participants' high expectations for quantum computers. I felt that by continuing to promote them in such settings, paired with concrete applications like "Quantum computers seem useful for catalyst discovery!", we could increase the number of fellow researchers eager to use them. This, in turn, could accelerate the aforementioned steady research and development. Next year's SC26 will be held in Chicago[6]. I hope we can all work together to advance our research and development so that we can demonstrate even more applications next year.
References
[1] https://pr.fujitsu.com/jp/news/2025/04/22.html
[2] https://global.fujitsu/ja-jp/pr/news/2025/08/01-01
[3] https://sc25.supercomputing.org/
[4] Hiroshi Sampei, Tetsuya Mizuguchi, Koki Saegusa, Makoto Nakamura, Koichi Kimura, Yasushi Sekine, "Multidimensional quantum Fourier transform for nanosheet material evaluation by electron microscopy: a case of 2D pattern processing," Physical Chemistry Chemical Physics, Mar. (2025)
[5] Hiroshi Sampei, Koki Saegusa, Kenshin Chishima, Takuma Higo, Shu Tanaka, Yoshihiro Yayama, Makoto Nakamura, Koichi Kimura, Yasushi Sekine, “Quantum Annealing Boosts Prediction of Multimolecular Adsorption on Solid Surfaces Avoiding Combinatorial Explosion,” JACS Au, 3, 4, 991-996 (2023)
