Phase-matched second-harmonic generation via laser plasma interaction

When an intense laser pulse interacts with homogeneous plasma in the presence of a transverse, spatially distributed static electric field, a transverse current density oscillating at a frequency twice that of the laser pulse is set up. This leads to the generation of second-harmonic radiation. The periodicity of the applied static electric field allows the second-harmonic radiation to be phase-matched. It is shown that under phase-matched conditions, the efficiency of the second-harmonic radiation in the presence of the spatially distributed static electric field is significantly enhanced as compared to that obtained for a uniform static electric field. Copyright (C) EPLA, 2015