相对论质量修正效应对超高次谐波的影响

Mass shift effect on relativistic high-order harmonic generation

通过分别求解含时狄拉克方程和含时薛定谔方程,研究了一维模型原子在相对论超强激光脉冲作用下的超高次谐波发射过程.研究结果表明:在弱场强条件下,相对论的模拟结果可以退化到非相对论的结果;随着场强的增强,可以逐渐观察到明显的相对论质量修正效应.此外,根据发展的相对论的"三步"模型并结合小波时频分析方法,分析了谐波平台的截止位置和发射效率.

By solving the time-dependent Dirac and Schr6dinger equations, we investigate the super high-order harmomc generation （HHG） from a one-dimensional model atom in a relativistic intense laser pulse. Our numerical simulations show that the relativistic results can be degraded to non-relativistic ones in the weak laser field, and the clear effect of the relativistic mass-shift can be gradually observed as the increase of the laser field intensity. Furthermore, the cutoff frequency and the emission efficiency of the HHG spectrum are analyzed by the wavelet time-frequency analysis and the relativistic ＂three-step＂ model.