Abstract-High-power terahertz radiation generation by beating of two co-propagating super-Gaussian laser beams in cluster plasma

Ram Kishor Singh, Monika Singh and Satish Kumar Rajouria

http://iopscience.iop.org/article/10.1088/1555-6611/aabffd

This communication presents the theoretical investigation of resonant terahertz (THz) radiation generation by two co-propagating laser beams having super-Gaussian intensity profile in a clustered plasma. The cluster electrons experience a ponderomotive force at beat wave frequency in the axial direction as well as perpendicular to the propagation direction of the beams due to the nonuniform intensity profile of laser beams. This force causes the acquisition of a nonlinear oscillatory velocity to the cluster electrons. A strong nonlinear transverse current density at beat wave frequency arises on account of the coupling of nonlinear velocity with density ripple, which drives a THz wave in the propagation direction of the laser beam. The THz yield strongly depends on the index of the super-Gaussian beams as well as the amplitude of density ripple. We report generated THz wave efficiency of 10−3 with the help of the optimizing laser beams and cluster plasma parameters.