Enhanced self-focusing of q-Gaussian laser beam in underdense plasma under the combined effect of density ramp and axial magnetic field

In this manuscript, we observed the synergistic potential of an exponential plasma density ramp and an axial magnetic field to enhance the self-focusing of q-Gaussian laser beams (q-GLB). Our study includes the derivation of the equation governing the beam width parameter, using the Wentzel-Kramers-Brillouin (WKB) and paraxial ray approximations for a comprehensive analysis. It is found that the forward magnetic field enhances self-focusing, while the reverse magnetic field weakens it in underdense plasma when compared to unmagnetized case. The combination of these optical parameters significantly improves self-focusing, resulting in a narrower beam with higher intensity at the focal spot. This leads to more efficient energy transfer to the plasma. The q-parameter determines the non-Gaussian degree and influences the formation of filaments in the beam. This approach can also mitigate the negative effects of diffraction and dispersion, leading to greater precision and efficiency in laser-plasma interaction. In the realm of laser-plasma interactions, the study’s findings, have direct applications in enhancing the precision and efficiency of high-power q-Gaussian laser systems, offering advancements in laser-driven fusion, plasma heating, and particle acceleration. By shedding light on the non-Gaussian behaviour of the system and the combined influence of the external factors, this research opens up new avenues for innovation and exploration in the field.