Development of a Power-Modulated Laser System with Long Pulse Duration and Its Application to Plasma Diagnostics

长脉冲功率调制激光系统的研制及其在等离子体诊断中的应用

• 批准号: 02452272
• 负责人: TSUKISHIMA Takashige
• 金额: $ 3.84万
• 依托单位: School of Engineering,Nagoya University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (B)
• 财政年份: 1990
• 资助国家: 日本
• 起止时间: 1990 至 1992
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-02452272/
• 关键词: power-modulated laser; injection locking; excitation of electrostatic waves; driven scattering method; electrostatic ion cyclotron wave; efficiency of the wave excitation; theoretical analysis; computer simulation; ハイブリッド粒子コード; ポンデロモーティブ力; ポンデロモ

The objective of the present study is to prove the principles of the driven scattering method which has been proposed as a novel scheme for high temperature plasma diagnostics. In the driven scattering, a power-modulated laser beam is injected into the plasma to excite electrostatic waves. Certain plasma parameters can be evaluated from the dispersion character of the excited waves.In 1990, a power-modulated TEA CO_2 laser system was developed. Two-mode pulse injection locking scheme was adopted and a power-modulated (the modulation frequency of 30MHz, 10J-class outputs with long pulse durations of the order of 1mus were obtained with high probability.In 1991, electrostatic ion cyclotron waves were excited in a laboratory plasma by making use of the power-modulated laser system developed in 1990. Langmuie probes were used to detect the plasma waves. A newly developed numerical filter having a narrow bandwidth was used to extract the wave signal from noisy background. The dispersion character of the excited waves was consistent with the dispersion relation of the electrostatic ion cyclotron wave.In 1992, the wave amplitude obtained in the experiment was compared with those predicted by a theoretical analysis and computer simulation. The wave amplitude obtained experimentally roughly agreed with the theoretical value within an order of magnitude, while the simulation result agreed well with the theoretical value.

本研究的目的是证明的驱动散射方法已被提出作为一种新的方案，用于高温等离子体诊断的原则。在驱动散射中，将功率调制的激光束注入等离子体以激发静电波。1990年研制了一套功率调制的TEA CO_2激光器系统。采用双模脉冲注入锁定方案，高概率地获得了功率调制（调制频率30MHz，脉宽1 μ s量级）的10J级输出，并于1991年利用1990年研制的功率调制激光系统在实验室等离子体中激发出静电离子回旋波。用朗缪尔探针探测等离子体波。采用一种新研制的窄带数字滤波器从噪声背景中提取海浪信号。激发波的色散特性与静电离子回旋波的色散关系相一致，1992年将实验得到的振幅与理论分析和计算机模拟的结果进行了比较。实验测得的波幅值与理论值在一个数量级内基本吻合，而仿真结果与理论值吻合较好。

项目成果

K.Sasaki et al.: "Development of a High-Power,Power-Modulated TEA CO_2 Laser System as a Driving Source of Electrostatic Plasma Waves" Proceedings of 2nd International Conference on Millimeter Wave and Far-Infrared Technology. 132-135 (1992)

K.Sasaki等人：“作为静电等离子体波驱动源的高功率、功率调制TEA CO_2激光系统的开发”第二届毫米波与远红外技术国际会议论文集。

K.Sasaki, T.Fujii, K.Takahashi, M.Nagatsu, and T.Tsukishima: "Excitation of Electrostatic Ion Cyclotron Waves by a Power Modulated Transversely Excited Atmosphere (TEA) CO_2 Laser" Phys. Fluids B: Plasma Phys.Vol.5. (1993)

K.Sasaki、T.Fujii、K.Takahashi、M.Nagatsu 和 T.Tsukishima：“功率调制横向激发大气 (TEA) CO_2 激光器对静电离子回旋波的激发”。

K.Sasaki: "Pulse InjectionーLocked TEA CO_2 Laser for Long Pulse Operation with Feedback Stabilization" Japanese Journal of Applied Physics. 29. 1459-1465 (1990)

K.Sasaki：“具有反馈稳定功能的脉冲注入锁定 TEA CO_2 激光器”，《日本应用物理学杂志》29. 1459-1465 (1990)。

K.Sasaki et al.: "A High-Power.Power-Modulated TEA CO_2 Laser System as a Driving Source of Electrostatic Plasma Waves" Rev.Sci.Instrum.63. 4086-4091 (1992)

K.Sasaki 等人：“作为静电等离子体波驱动源的高功率功率调制 TEA CO_2 激光系统”Rev.Sci.Instrum.63。

K.Sasaki et al.: "Excitation of Plasma Waves by a Power-Modulated TEA CO_2 Laser" Proceedings of International Symposium on Laser-Aided Plasma Diagnostics. 122-127 (1991)

K.Sasaki 等人：“功率调制 TEA CO_2 激光器激发等离子体波”激光辅助等离子体诊断国际研讨会论文集。