Progress in Extending the High-Temperature Plasma Regime in the LHD
In this paper, we show the expansion of the high-temperature regime and related physical phenomena in the Large Helical Device (LHD). At the LHD, we have developed a high-temperature operational regime for both ion (Ti) and electron (Te) temperatures through understanding the physical characteristics of high-temperature plasma, the enhancement of plasma heating, and the development of technical methods such as wall recycling control and impurity control. In particular, the formation of the ion internal transport barrier (i-ITB) and electron internal transport barrier (e-ITB) in the plasma core region is the key to improving plasma performance. In addition, the deuterium experiment that began in 2017 showed that, due to the isotope effect, the thermal transport of both ions and electrons is suppressed in deuterium plasma compared to light hydrogen plasma, and that a high central temperature can be achieved efficiently. Furthermore, the combination of neutral beam injection (NBI) and electron cyclotron heating (ECH) has extended the operating conditions that simultaneously maintain high Ti and Te, and comprehensive research on plasma confinement characteristics with an eye to future fusion reactor conditions has progressed.
Authors
- R. Yanai (ORCID: https://orcid.org/0000-0002-4501-1956)
- M. Nakata (ORCID: https://orcid.org/0000-0003-2693-4859)
- F. Nespoli (ORCID: https://orcid.org/0000-0001-7644-751X)
- K. Mukai
- K. Ida
- K. Tanaka
- S. Kamio
- T. Morisaki
- H. Takahashi
- M. Yokoyama
- A. Shimizu
- S. Kubo
- M. Kobayashi
- H. Nakano
- T. Seki
- S. Murakami
- K. Saito
- T. Ii. Tsujimura
- H. Igami
- N. Kenmochi
- H. Yamaguchi
- M. Goto
- T. Ido
- M. Yoshinuma
- T. Oishi
- H. Funaba
- F. Warmer
- N. B. Marushchenko
- Y. Yoshimura
- I. Yamada
- Y. Turkin
- Y. Kawamoto
- K. Nagaoka
- T. Kobayashi
- T. Tokuzawa
- M. Osakabe
- R. Seki
- S. Masuzaki
- H. Kasahara
- Y. Fujiwara
- G. Motojima
Institutions
- ITER (FR)
- Kyushu University (JP)
- ROHM (JP)
- Chubu University (JP)
- National Institutes of Natural Sciences (JP)
- The Graduate University for Advanced Studies, SOKENDAI (JP)
- Tohoku University (JP)
- University of California, Irvine (US)
- Kyoto University (JP)
- Princeton Plasma Physics Laboratory (US)
- Japan Science and Technology Agency (JP)
- National Institute for Fusion Science (JP)
- National Institutes for Quantum Science and Technology (JP)
- Max Planck Institute for Plasma Physics - Greifswald (DE)
- Kyoto University of Education (JP)
- Nagoya University (JP)
- Komazawa University (JP)
- TAE Technologies, Inc (United States) (US)
Publication Details
- Journal
- Journal of Fusion Energy
- Published
- 2026-04-06
- DOI
- https://doi.org/10.1007/s10894-026-00571-1
- Primary Topic
- Magnetic confinement fusion research
- Type
- article
- Field-Weighted Citation Impact
- 0.00