超短脉冲强激光场中电子剩余能计算

为了控制光场感应电离等离子体的温度以使得基于光场感应电离机制的X射线激光辐射获得更高的增益值，利用准静态隧道电离模型，定量计算了电子剩余能量与激光偏振参量、波长(频率)、激光强度以及电离介质电离能的变化关系。计算结果表明线偏振短波长激光以及高电离能介质产牛的等离子体中电子剩余能比较低，因此适合用作复合机制X射线激光；对于低价离子存偏振度α介于0～1之间的某一处最高，因此，可以通过调整偏振度α，获得某一椭圆偏振光，会更有利于基于光场感应电离电子碰撞机制X射线激光增益的提高。

The Calculation of Electron Residual Energy in an Intense Laser Field

In order to obtain high gain X-ray laser based on the optical field ionization (OFI) induced plasmas, the electron temperature in OFI plasma must be controlled. The dependence of the electron residual energy on laser parameters such as polarization, wavelength (frequency), laser intensity and media ionization potential is calculated quantitatively using quasistatic tunneling ionization model. According to the calculated results it is noted that the electron residual energy is lower either the short-wavelength laser with linear polarization or the medium with high ionization potential is used, thus it is suitable for recombinational mechanism; the residual energy is highest when the polarization α is at some value of 0～1, thus the value of polarization α can be tuned and some elliptical polarized laser can be obtained, which may be in favor of the realization of electron-collisional X-ray laser. So higher gain values can be got.