Picosecond laser-driven terahertz radiation from large scale preplasmas of solid targets

9th International Conference on Inertial Fusion Sciences and Applications

Liao, G.Q.^1 ; Li, Y.T.^1,4 ; Li, C.^1 ; Su, L.N.^1 ; Zheng, Y.^1 ; Liu, M.^1 ; Dunn, J.^2 ; Nilsen, J.^2 ; Hunter, J.^2 ; Wang, W.M.^1,4 ; Sheng, Z.M.^3,4,5 ; Zhang, J.^3,4

Beijing National Laboratory for Condensed Matter PhysicS, Institute of Physics, Chinese Academy of Sciences, Beijing

100190, China^1

Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore

CA

94551, United States^2

Key Laboratory for Laser Plasmas (MoE), Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai

200240, China^3

Collaborative Innovation Center of IFSA (CICIFSA), Shanghai Jiao Tong University, Shanghai

200240, China^4

SUPA, Department of Physics, University of Strathclyde, Glasgow

G4 0NG, United Kingdom^5

关键词: Laser energies;    Mode conversions;    Normal direction;    Particle-in-cell simulations;    Specular direction;    Terahertz radiation;    Transient current;    Vacuum interfaces;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/717/1/012105/pdf
DOI  :  10.1088/1742-6596/717/1/012105

来源: IOP

【 摘 要 】

The terahertz (THz) radiation from the front of solid targets with a large-scale preplasma irradiated by relativistic picosecond laser pulses has been studied. The THz radiation measured at the specular direction nonlinearly increases with laser energy and an optimal plasma density scalelength is observed. Particle-in-cell simulations indicate that the radiation can be attributed to the model of mode conversion. While the THz radiation near the target normal direction is saturated with laser energy and plasma scalelength. Unlike the radiation in the specular direction' the transient current formed at the plasma-vacuum interface could be responsible for the radiation near the target normal.