Electron Acceleration by Chirped Mono-and Bichromatic Laser Pulses in Underdense Plasmas
We investigate the properties of laser-driven electron acceleration in underdense plasmas in the confines of an effective theory. Here we treat the plasma as a continuous medium, described with its index of refraction. The acceleration processes have been studied by numerically solving and analysing the classical, relativistic equations of motion. The index of refraction has been incorporated into the plane wave argument of the driver laser field.
We calculated the energy gain of a single electron by a single monochromatic infra-red laser pulse and compared our results with experimental data and more sophisticated PIC simulations. We found a satisfactory agreement. We also investigated the effects of mixing the second harmonic to the driver pulse and found that this may increment the final energy of the electron by ten percent or even more. We also investigated the accuracy of the paraxial approximation by using a Maxwell–Gaussian pulse shape as well.