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波长１．０５３μｍ、脉宽约１ｎｓ、能量３００～６００Ｊ激光在亚毫米的腔靶中可以产生十分丰富的非线性过程。我们直接测量了受激Ｂｒｉｌｌｏｕｉｎ散射、受激Ｒａｍａｎ散射：通过谐波间接测量了共振吸收、离子声衰变和双等离子体衰变。其中受激Ｂｒｉｌｌｏｕｉｎ散射和受激Ｒａｍａｎ散射是腔靶中的主要非线性过程，它散射掉约４０％的入射光能量。激光激发的电子等离子体波是产生超热电子的根源，产生电子等离子体波的非线性过程是受激Ｒａｍａｎ散射、双等离子体衰变、共振吸收和离子声衰变。其中受激Ｒａｍａｎ散射是激发电子等离子体波的主要过程，它产生约占入射激光能量１０％的超热电子。各非线性过程发射的光谱与激光参数和等离子体状态有密切关系，仔细测量和研究这些谱的特性可以获得等离子体温度、密度的信息。
Wavelength of 1.053μm, pulse width of about 1ns, energy 300 ~ 600J laser in the sub-millimeter cavity target can produce a very rich non-linear process. We directly measure stimulated Brillouin scattering, stimulated Raman scattering: Resonance absorption, ionophoretic decay, and double plasma decay are indirectly measured by harmonics. Among them, stimulated Brillouin scattering and stimulated Raman scattering are the main non-linear processes in the cavity target, which scatter about 40% of incident light energy. The laser-excited electron plasma wave is the source of superheated electrons. The nonlinear process of generating electron plasma waves is excited Raman scattering, double plasma decay, resonance absorption and ion acoustic decay. Among them, the stimulated Raman scattering is the main process that excites the plasma wave. It produces superheated electrons that account for about 10% of the incident laser energy. The spectra emitted by each nonlinear process are closely related to the laser parameters and the plasma state. Careful measurement and study of the characteristics of these spectra can provide information about the plasma temperature and density.