[en] A series of coupling equations for the relativistic coherent harmonic generation is derived taking account of the coupling effect among the harmonic contents and plasmas wave. Using these equations, the growth and saturation of amplitude of the third harmonic wave is investigated. Results show that the coupling effect induces the saturation of harmonics, which is identical with ones of the Lagrangian description

[en] Stimulated Raman sidescattering (SRSS), especially 90° sidescattering, can play a dominant role in inhomogeneous plasma. Here, we study the SRSS eigenmode excited in steep-gradient plasma on both numerical and theoretical aspects. Particle-in-cell simulations show that strong SRSS eigenmode are excited even when the plasma scale length at the critical density is as short as one laser wavelength. The studies of the dependence of SRSS on scale length show that there is a minimum scale length to ensure the scattered light strong enough to be observed efficiently. And with the plasma scale lengthening the frequency of scattered light gradually approaches the half of the frequency of incident laser pulse. The linear theory about the growth of SRSS in inhomogeneous plasma shows a good agreement with the simulation, which indicates that the linear theory is also generally right for the case of steep-gradient plasma. When ion motion is considered in the simulations, plasma curvature caused by pondermotive force has a significant effect on the properties of scattered light. Moreover, it is found that short plasma density scale lengths can be identified qualitatively based on SRSS eigenmode in the steep-gradient plasma. (paper)

[en] By using the theory of configuration-interaction, authors made a analysis of the effect of configuration interaction on the autoionization rates and branch ratios of the configurations 2p⁵ 3s3l(l = 0, 1, 2) for the Na like Cu ion. It is shown that the autoionization rates in all the three configurations are changed substantially when the configuration-interaction are included in comparing with the calculations in single-configuration approximation, and the branch ratios increase both in the configuration 2p⁵3s3d and in 2p⁵3s3p but decrease in the configuration 2p⁵3s²

[en] The characteristics of high-order relativistic harmonic generation excited by intense laser pulse in underdense plasmas is investigated. With quasistatic approximation, the growth and saturation of N^th-order relativistic harmonics are analyzed, and the ratio of high-order power to fundamental wave power is described and calculated

[en] The results of experimental and theoretical study on population inversion in the He-like Al ions are presented for the pumping laser intensity range of ∼ 2 x 10¹⁴ W/cm². The effects of different target structure (foil, plane and half-cylinder) on the 2p-3d population inversion of the He-like Al ions (45 nm) in a spot focused laser plasma have been studied experimentally. The plasma parameters such as electron temperature, electron density and the ratio of H-like ion density to He-like ion density, are diagnosed by spectroscopic methods. Results are compared with C-R model calculations

[en] An equation for self-generated magnetic field is derived, and is used to investigate the self-generated magnetic field produced by an intense short laser pulse in pre plasma channel. The results show that the magnetic field can be generated by the ponderomotive mechanism, and the cavitation influences the magnetic field. The structure of the magnetic field in a plasma channel is also demonstrated

[en] The self-generated magnetic field induced by an ultra-intense short laser pulse propagating in a uniform underdense plasma is investigated. The magnetic fields are strong and associated with the plasma wave wake field. Some properties of dc magnetic field in two extreme laser pulse regime are described

[en] With numerical calculations, the plasma conditions, in which the laser gains of 1s3d ¹D2 - 1s2p ¹P1 transition of He-like aluminum ions can be produced, have been obtained. The method of radiative cooling used to produce the necessary plasma conditions has also been proposed and simulated

[en] Through analysing the spatial distribution characteristics of the linewidth of Li-like silicon ions X-ray lasers, it is shown that Stark broadening is the main line broadening mechanism for Li-like Si¹¹⁺ ions recombine X-ray laser. Spatial distribution of the electron density of gain medium obtained by Stark broadening shows that the electron density in the gain region is about 10¹⁹/cm³, and the lasing linewidth and electron density are 0.21 A and 2.9 x 10¹⁹/cm³ at the gain maximum respectively

[en] The simulation of X-ray laser has been performed for Li-like silicon, pumped by the 116 ps laser pulse, with the intensity of 6.5x10¹² W/cm² and the wavelength of 1.06 μm. The populations of energy level 4f and the gains of transition 4f-3d of Li-like silicon ions have been obtained as a function of time. The results have been explained and compared with experiment