Promotion of interdisciplinary research through UNIT
Address the “unsolved problems” of fusion science through “academic formulation” of them, by establishing the “interdisciplinary joint research structure.”
| UNIT | Axis | Theme |
| Meta-hierarchy Dynamics | Dynamics, Space-time | The key to improving the performance of fusion plasmas is to control the spontaneously generated fluctuations and structures with various scales. To this end, it is necessary to construct physical models that express complex phenomena in which micro- and macroscopic scales are interconnected and to elucidate the universal mechanisms inherent in these phenomena. By reconsidering dynamics from a meta-perspective that does not presuppose the predetermined hierarchical separation and clarifying the similarities and differences with other complex systems, such as living organisms and economic systems, we will establish a new academic theory from fusion science to the science of collective phenomena. |
| Structure Formation and Sustainability | System | Improving plasma confinement and steady-state operation are central challenges in research to make fusion reactors more efficient and compact. The key is to understand the mechanism by which plasmas spontaneously form and maintain their internal structure. We elucidate the principles of structure formation by revisiting fundamental physics concepts such as symmetry and entropy. Based on this, we explore high-performance confined configurations. Structure formation in plasmas is a common phenomenon in celestial bodies such as magnetospheres and accretion disks and is a fundamental theory for understanding the universe. |
| Phase Space Turbulence | Fluctuation, Turbulence, Transportation |
To realize an economical fusion reactor, high-performance core plasma is required. One factor that determines the plasma performance is the plasma heat conduction and transport due to turbulence. Focusing on the diversity of motion of particles that constitute plasma, we will elucidate the mechanism of fluctuations (micro-collective phenomenon) and turbulent transport generated by particles. The physics of micro-collective phenomena will be the guiding principle of nuclear fusion innovation and, simultaneously, the fundamental theory of non-equilibrium and non-linear physics that underlies other plasma phenomena such as space and celestial bodies. |
| Plasma Quantum Processes | Elementary process, Interaction |
In a fusion system, various physical phenomena occur that cannot be described by a collective motion model of particles that do not have internal degrees of freedom. We aim to construct physical models of non-equilibrium and high-density plasmas by precisely treating quantum processes that govern changes in electronic states in particles, interactions with electromagnetic waves, and effects such as spin. This problem is a universal one common to astronomical and space plasma physics and nuclear physics, leading to new developments in plasma quantum processes. |
| Transports in Plasma Multi-phase Matter System | Different-phase coupled phenomena | The enormous thermal and particle loads on the divertor are a significant problem in fusion reactors. We delve into physical mechanisms under extreme conditions to study interactions between plasmas and different phases of matter: gas, solid, and liquid. Using experiments with torus and linear plasma devices and computer simulations, we will elucidate the complex transport phenomena and clarify the conditions for a fusion reactor. Study of the interaction between plasma and different phases is common to research on the interaction between plasma and matter in space. It will also lead to the elucidation of the physical and chemical processes of the creation of matter, which is the basis of life. |
| S&I: Sensing and Intellectualizing Technology | Measurement, Data |
Observing, predicting, and controlling the behavior of ultra-high temperature plasma are essential subjects for improving the performance of fusion reactors. We will develop dramatically high-precision plasma measurement methods and construct a system that enables holistic and precise plasma observation. Furthermore, we will analyze the data using data science and convert it into visual, auditory, tactile, and other information to make it “intellectualizable”. This effort, in which researchers specializing in measurement, data analysis, and expression methods work together to systematize the intellectual inquiry process, will revolutionize the understanding of phenomena in fusion science and many other scientific fields. |
| Plasma Apparatus | Device Science, Technology |
The importance of disruptive innovation, a game changer in fusion research, has been pointed out. To this end, it is necessary to take on the challenge of creating innovative plasma technologies by deepening the academic knowledge of the complex collective phenomena of plasma. By making novel applications of plasma, not limited to fusion cores, a working hypothesis, we will promote collaboration and union with other fields and shed light on the unexplored emergent nature of collective phenomena. Innovations in plasma device science will open up new horizons for various natural science research and science and technology. |
| Complex Global Simulation | Computing science | Simulation studies are essential in elucidating the complex phenomena occurring inside fusion plasmas. In ultra-high temperature plasma, macroscopic fluctuations emerge from microscopic particle motions. We aim to accurately predict fusion burning plasmas by developing an original idea of computational methods that link multiple hierarchies and utilize data science to simulate the entire plasma. This method can also be applied to space and astronomical plasmas, opening up new prospects for simulation science. |
| Ultrahigh-flux Concerting Materials | Material science | Material degradation due to ultrahigh-flux of particles and heat can be the Achilles heel of fusion reactors. To solve the core issue of fusion reactors, which is to improve the durability of reactor materials, a deep understanding of condensed matter physics related to material degradation and control techniques is necessary. We aim to change the conventional idea of suppressing alteration, consider the enhancement and function factors that appear only when the load is large as “adaptation,” and create materials that change themselves and work in concert with ultrahigh-flux. This approach will lead to innovations in nuclear, space, aviation, and chemical plant materials where harsh environments are inevitable. |
| Applied Superconductivity and Cryogenics | Cryogenics | Innovations in superconductivity and cryogenic technology have great potential to be game-changers in fusion research. In order to put advanced superconducting materials such as high-temperature superconductors to practical use as magnets for nuclear fusion reactors, we are working on technologies for making wires and large current conductors, coil system technologies that can stably generate strong magnetic fields, promoting research on economic refrigeration technology using hydrogen, and basic technology on production and utilization of hydrogen. Technological innovations in superconductivity and hydrogen utilization will contribute widely to realizing a carbon-neutral and energy-sustainable social environment. |