Chinese Journal of Computational Physics ›› 2023, Vol. 40 ›› Issue (2): 248-257.DOI: 10.19596/j.cnki.1001-246x.8613

Special Issue: 贺贤土院士从事科学研究工作60周年暨激光聚变相关研究进展专刊

• The 60th Anniversary of Academician He Xiantu's Scientific Research Work: A Special Issue of Research Progress in Laser Fusion • Previous Articles     Next Articles

Solution of Wigner-Poisson System with Combining Flux Balance and Fourier Spectrum Methods

Tianxing HU1, Zhengmao SHENG1,*(), Dong WU2,*()   

  1. 1. Institute of Fusion theory and simulation, School of Physics, Zhejiang University, Hangzhou, Zhejiang 301400, China
    2. Collaborative Innovation Center of Inertial Fusion Science and Applications, School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China
  • Received:2022-08-15 Online:2023-03-25 Published:2023-07-05
  • Contact: Zhengmao SHENG, Dong WU

Abstract:

The difference between quantum plasma and classical plasma is mainly reflected in the following two aspects: 1) the statistical equilibrium state of the system changes from the classical Maxwell distribution to the Fermi-Dirac distribution; 2) the single-particle quantum wave effect of electrons cannot be avoided. Corresponding to the Vlasov equation in the classical plasma, the kinetic equation of the quantum plasma is the Wigner equation, but the numerical solution of the Wigner equation is more complicated than the Vlasov equation. In this paper, we propose a new method based on flux balance and Fourier spectrum methods. The hybrid method is used to solve the Wigner-Poisson equations. This method adopts different time advancing algorithms in the coordinate and velocity spaces. Compared with the general discrete Euler method, it can significantly improve the accuracy of nonlinear simulation results. This paper investigates the behavioral changes of some common electrostatic kinetic instabilities in quantum plasmas through this method; verifies the reliability of the code through linear eigensolutions, and then simulates some nonlinear phenomena, including Nonlinear Landau damping and nonlinear saturation for two-stream instability, etc.

Key words: quantum plasmas, kinetic, Euler method, nonlinear effects