Significant enhancement in self-focusing of high-power laser beam through dense plasmas by ramp density profile

Abstract

The effect of the ramp density profile on relativistic self-focusing of a cosh-Gaussian (ChG) laser beam in dense plasmas is investigated. For this purpose, a modified refractive index of inhomogeneous cold quantum plasma (ICQP) with the inclusion of quantum correction in the relativistic regime is considered. Contrary to earlier works on self-focusing of laser beams through quantum plasmas, higher-order terms in the expansion of the dielectric function and the eikonal are taken into account. In this situation, the envelope equation governing the beam-width parameter is derived in the cylindrical coordinate system. Particularly, the self-focusing feature and the sensitivity of decentered parameter b for the ChG laser beam in the ICQP are also illustrated by utilizing a higher-order paraxial theory. The results are presented graphically and discussed.