Introduction to the Institute for Fusion Theory and Simulation (IFTS)

I. Background and Establishment

Energy is a major strategic concern for the sustainable development of China’s national economy. Fusion energy, characterized by abundant fuel resources, negligible greenhouse gas emissions, low radioactivity, and minimal environmental impact, is widely regarded as an ideal long-term energy solution.

Major international efforts, such as the International Thermonuclear Experimental Reactor (ITER), are advancing magnetic confinement fusion, with China participating as one of its seven partners. In parallel, inertial confinement fusion has been identified as a key national priority in China’s Medium- and Long-Term Science and Technology Development Plan.

Addressing these challenges requires sustained advances in both fundamental research and talent development. In particular, the cultivation of young plasma physicists is of critical importance. Against this background, the Institute for Fusion Theory and Simulation (IFTS) at Zhejiang University was established on October 23, 2006, under the leadership of Academician Xiantu He, and with joint support from Zhejiang University, the Southwestern Institute of Physics, the Institute of Plasma Physics (Chinese Academy of Sciences), and the National High tech R&D Program (863 Program). Professor Liu Chen served as its first Director.

Since 2006, under the leadership of Professor Chen, IFTS has developed into an influential center for plasma theory and simulation both domestically and internationally. In 2016, following a global recruitment process, Professor Guoyong Fu joined Zhejiang University and assumed the position of Director of the institute, continuing the institute’s tradition of education and frontier research.

II. Mission and Research Areas

The Institute’s mission is to advance plasma physics research, cultivate the next generation of scientists, and establish IFTS as a world-class center for fusion science.

IFTS conducts research across a broad range of areas, primarily focusing on magnetic confinement fusion, while also encompassing inertial confinement fusion and space plasma science. Research efforts are directed towards theory and simulation of Alfvén waves, energetic particles, MHD instabilities and turbulent transport in magnetically confined fusion plasmas, development of large-scale simulation codes, as well as laser-plasma interaction, relativistic discharges, and design of innovative magnetic confinement devices.

III. Faculty and Personnel

The institute currently comprises 6 professors, 3 assistant professors, and 2 adjunct professors, namely Professors Liu Chen, Guoyong Fu, Zhengmao Sheng, Zhiwei Ma, Yong Xiao, and Huichun Wu, Assistant Professors Wei Zhang, Xinglong Zhu, and Hongxuan Zhu, Adjunct Professors Fulvio Zonca and Min Xu. The institute also has over 30 graduate students. Courses offered by IFTS faculty members include Electrodynamics, Physics and Human Civilization, and University Physics for undergraduates, as well as specialized graduate courses such as Basic Plasma Physics and Advanced Plasma Physics I, II and III.

IV. Achievements and Contributions

Since its founding in 2006, IFTS has made significant contributions to education and plasma physics research. In the area of education and training of students, a total of 89 graduate students have graduated and 48 of them have continued research in plasma physics and fusion science at research institutes and universities. In research, over 800 papers have been published in peer-reviewed journals including Reviews of Modern Physics, Physical Review Letters, Geophysical Research Letters, Nuclear Fusion, and Physics of Plasmas. Some examples of notable research achievements are as follows:

1. Theory and Simulation of Magnetically Confined Fusion Plasmas

   1. Established the theoretical framework of the general fishbone-like dispersion relation (GFLDR) that provides a unified approach for linear and nonlinear analysis of Alfvén eigenmodes and Energetic Particle Mode (EPM) [1,2,3];

   2. Developed systematic nonlinear theories of Toroidal Alfvén eigenmodes (TAEs) driven by energetic particles in tokamak plasmas [1] that showed important role of zonal current [4] and the nonlinear decay process of TAE into a geodesic acoustic mode and kinetic TAE in toroidal plasmas [5];

   3. Investigated the effects of zonal (electromagnetic) fields on the energetic particle's (EPs) drive of reversed-shear Alfven eigenmodes (AEs) in tokamak plasmas. Contrary to the conventional expectation, analytic theory and simulation results showed that zonal fields further enhance the instability drive and thus lead to a higher saturation level [6];

   4. Developed a nonlinear toroidal MHD simulation code CLT [7,8] and its kinetic-MHD hybrid version CLT-K [9]. The codes have been successfully applied to study Hall effects on tearing instabilities [10] and energetic particle interaction with tearing modes [11] in tokamak plasmas;

   5. Developed a nonlinear toroidal gyrokinetic-MHD energetic simulation code GMEC [12,13] and its GPU version cuGMEC. The code has been successfully applied to efficiently simulate nonlinear evolution of alpha particle-driven high-n Alfvén eigenmodes and alpha particle transport in ITER;

   6. Gyrokinetic simulation of the edge turbulent transport in toroidal plasmas found a reverse trend in the turbulent transport coefficients under strong gradients. The results suggest a completely new mechanism for the low to high confinement mode transition without invoking shear flow or zonal flow [14];

   7. Extended the gyrokinetic simulation code GTC for simulating turbulent transport in tokamaks with realistic equilibrium profiles and plasma geometry [15].

2. Experimental Research

   1. Propagation dynamics associated with Resonant Magnetic Perturbation fields in H-mode plasmas of the KSTAR tokamak were measured and analyzed for the first time [16];

   2. Upgraded the linear plasma experimental device at Zhejiang University (ZPED) with several diagnostics including a microwave reflectometry, a fast camera and Langmuir probes [17];

   3. Built a relativistic discharge experimental device (RDEX) for investigating high-energy physics of lightning, successfully performed hundreds of air discharge experiments, first detected beamed MeV photons.

3. Design of New Magnetic Confinement Devices

   1. Designed the compact stellarator with simple coil CSSC with four simple coils. The optimized stellarator has good neoclassical confinement and good MHD stability [18];

   2. Designed a linked mirror magnetic confinement device for laboratory experiments [19]. The design consists of two simple magnetic mirrors connected by toroidal coils thereby eliminating the particle end losses of simple mirrors [19];

4. High Energy Density Physics and Laser Plasma Interaction

   1. Developed a comprehensive theory for the ball lightning, a fireball sometimes observed during lightnings. The theory resolves the long-standing mystery of the ball lightning [20];

   2. Quantitatively demonstrated for the first time via PIC simulations how electromagnetic turbulence affects ion kinetics of counter-streaming plasmas under achievable laboratory conditions. The results have well explained the recent unmagnetized experimental observations [21];

   3. Proposed a scheme for beam-target p-11B fusions via injecting a MeV proton beam into a highly compressed quantum degenerated boron target, leading to an increase in fusion yield by orders of magnitude [22];

   4. Proposed a novel approach for the development of polarized lepton sources via collective beam-target interactions [23, 24].

5. Space Physics

   1. Proposed a phenomenological model called the "Trap-Release-Amplify" (TaRA) model for whistler mode chorus waves, resolving the long-standing problem of its frequency chirping [25];

   2. The effective resistivity model for collisionless magnetic reconnection was successfully applied in the 2.5D MHD and Hall MHD simulations, and the results agreed well with the particle-in-cell (PIC) simulations [26].

References

[1] L. Chen and F. Zonca, Review of Modern Physics 88, 015008 (2016).

[2] F. Zonca and L. Chen, Phys. Plasmas 21, 072120 (2014).

[3] F. Zonca and L. Chen, Phys. Plasmas 21, 072121 (2014).

[4] L. Chen and F. Zonca, Phys. Rev. Lett. 109, 145002 (2012).

[5] Z. Qiu, L. Chen, F. Zonca and W. Chen, Phys. Rev. Lett. 120, 135001 (2018).

[6] L. Chen, P. F. Liu, R. R. Ma et al., Nucl. Fusion 65, 016018 (2025).

[7] S. Wang and Z. W. Ma, Phys. Plasmas 22, 122504 (2015).

[8] W. Zhang, S. C. Jardin, Z. W. Ma et al., Computer Physics Communications 269, 108134 (2021).

[9] J. Zhu, Z. W. Ma and S. Wang, Phys. Plasmas 23, 122506 (2016).

[10] W. Zhang, Z. W. Ma, and S. Wang, Phys. Plasmas 24, 102510 (2017).

[11] H. W. Zhang, Z. W. Ma, J. Zhu, W. Zhang et al., Nucl. Fusion 62, 026047 (2022).

[12] P. Y. Jiang, Z. Y. Liu, S. Y. Liu, J. Bao and G. Y. Fu, Phys. Plasmas 31, 073904 (2024).

[13] Z. Y. Liu, P. Y. Jiang, S. Y. Liu, L. L. Zhang and G. Y. Fu, Phys. Plasmas 31, 073905 (2024).

[14] H. S. Xie, Y. Xiao and Z. Lin, Phys. Rev. Lett. 118, 095001 (2017).

[15] Y. Xiao, I. Holod, Z. X. Wang et al., Phys. Plasmas 22, 022516 (2015).

[16] W. W. Xiao, T. E. Evans, G. R. Tynan et al., Phys. Rev. Lett. 119, 205001 (2017).

[17] W. W. Xiao, C. Y. Wang, J. X. Zhu et al., AIP Advances 9, 075026 (2019).

[18] G. D. Yu, Z. C. Feng, P. Y. Jiang and G. Y. Fu, J. Plasma Phys. 88, 905880306 (2022).

[19] Z. C. Feng, G. D. Yu, P. Y. Jiang and G. Y. Fu, Nucl. Fusion 61, 096021 (2021).

[20] H. C. Wu, Sci Rep 6, 28263 (2016).

[21] P. Liu, D. Wu, T. X. Hu, D. W. Yuan, G. Zhao, Z. M. Sheng et al., Phys. Rev. Lett. 132, 155103 (2024).

[22] S. J. Liu, D. Wu, T. X. Hu et al., Phys. Rev. Research 6, 013323 (2024).

[23] X.-L. Zhu et al., Phys. Rev. Lett. 132, 235001 (2024).

[24] X.-L. Zhu et al., Phys. Rev. Research 6, L042069 (2024).

[25] X. Tao, F. Zonca and L. Chen, Journal of Geophysical Research: Space Physics, 126, e2021JA029585 (2021).

[26] H. W. Zhang, Z. W. Ma, and T. Chen, Journal of Geophysical Research: Space Physics, 130, e2025JA034289 (2025).