Enhanced harmonic generation by propagation of two-color p-polarized laser beams in plasma

Abstract

A theoretical model is developed for studying the generation of third-harmonic radiation by the interaction of obliquely incident, two-color p-polarized laser beams with spatially varying plasma density. The ratio of the fundamental frequencies of the two laser beams are considered to be an arbitrary integer. The amplitude of harmonic radiation obtained by oblique incidence of two-color laser fields propagating in homogeneous plasma is enhanced in comparison with that obtained by normal incidence of two-color laser beams. The periodicity of the plasma density allows the harmonic radiation to be phase-matched, leading to further increase in the amplitude of phase-matched harmonic radiation by an order of magnitude. The amplitude of the generated harmonic radiation increases with the increase in angle of incidence.

Generation and regulation of electromagnetic pulses induced by hybrid laser pulses interacting with solid targets

“…The energy of various particles is further converted to electromagnetic waves with a large frequency band from radiofrequency-microwaves to x-ray and γ-ray through collision and radiation [8][9][10][11]. Electromagnetic pulses (EMPs) induced by the laser interacting with solid targets have broad frequency domains ranging from tens of MHz to THz [12,13] and the intensity can reach kV m −1 even MV m −1 [14][15][16]. The giant EMPs contain significant information regarding laser interacting plasma, but they also severely inter-fere with various accurate physical diagnoses and sometimes cause the malfunction of some important diagnostic equipment [17,18].…”