Study Of Temporal-Spatially Evolution Characteristics Of Laser-Produced Al Plasmas

Laser produced plasma(LPP) is hot dense plasma which generated by focusing the intense laser to the target surface, we can obtain the atomic structure, plasma parameters and dynamic information through the temporal-spatially resolved spectra measurement. So far the laser produced plasma technique as an effective method has been widely used in the field of Astrophysics physics, nuclear fusion and lithography.There are abundant spectral lines of Al elements in astrophysics plasmas, and the study of the emission spectra of Al plasma is helpful for the diagnosis of the plasma. In addition, Al ionic emission lines in the EUV region were often taken as wavelength calibration of extreme ultraviolet spectrometer because of good line distributions.As the plasma is applied to more and more areas, understand the temporal and spatial evolution behavior of plasma, plays a crucial role in application of plasma. In this work, we study the evolution behavior of Al plasma in vacuum through experiment and theory. Mainly includes the following aspects:1. Designed and built a laser plasma measuring device has the advantages of simple operation and procedure-controlled, achieved the time and space resolution measurement of laser plasma. We also developed a control software system and realized intelligent control of laser plasma measuring device.2. Used the device to the temporal-spatially resolved measurement of laser produced Al plasma, the spectral measurement wavelength is 8.5 nm to 13.4 nm. Obtained the time resolved spectra of Al plasma in two different space of 0.5 mm and 1 mm, the delay time from 20 ns to 70 ns, and the space resolved spectra at the delay time of 30 ns, the spectrum of space detection range from 0 to 1.6 mm, step by 0.2 mm. In addition, the spectra of Al plasma in the spectral range were identified by the NIST database.3. Based on the assumptions of a normalized Boltzmann distribution among the excited states and a steady-state collision radiation(CR) model, the experiment spectra were simulated theoretically and the plasma parameters of each experimental condition were obtained. Finally, through the spectral simulation to investigate the spatial evolution characteristics of Al plasma provided the experimental and theoretical basis for the he related theoretical model.