Response to “Comment on ‘Electron acceleration by a chirped Gaussian laser pulse in vacuum’” [Phys. Plasmas 14, 044701 (2007)]

In their Comment, Gupta, Hur, and Suk have numerically investigated the acceleration of electrons by a circular chirped laser pulse in vacuum. In the Comment, Figs. 1–3 compare the electron energy for the case of linear¹ and circular polarizations. The results show that the circular polarization of the laser pulse could modify the efficiency of the absorption processes significantly. It can be attributed to the axial symmetry of the circular polarization of the laser pulse. As the authors of the Comment indicated, chirped laser electron acceleration in vacuum depends on the polarization of the laser pulse. It also seems that in the case of circular polarization, the electron circulates around the laser propagation direction. Therefore, the electron spend more distance in resonance with the chirped laser pulse. One can address such an effect to the recent work of Gupta and Suk.² In conclusion, it is expected that the circular polarization changes the electron trajectories and leads to an enhanced resonance absorption in a tailored initial parameter. Therefore, a considerable energy exchange between the electron and chirped laser pulse could occur.