Excitation of frequency overtones of self focused q-Gaussian laser beam in preformed collisional parabolic plasma channels: higher harmonic generation

This paper investigates the generation of higher harmonics from an intense, self-focused q-Gaussian laser beam propagating through a preformed, collisional parabolic plasma channel. The theoretical framework leverages the nonlinear Schrodinger equation (NLSE) to model the beam propagation and self-focusing dynamics due to the interplay between the laser field and the plasma electrons. We explore the dependence of higher harmonic generation efficiency on various parameters, including the laser beam intensity, the plasma density, and the channel depth. Our analysis focuses on how the self-focusing behavior of the q-Gaussian laser beam, influenced by these parameters, affects the generation of frequency overtones through nonlinear processes within the plasma channel. The results shed light on the optimal conditions for achieving efficient higher harmonic generation in this specific scenario. This knowledge can be valuable for various applications that rely on intense, high-frequency radiation, such as attosecond pulse generation, extreme ultraviolet and X-ray sources, and advanced material characterization techniques.