Relativistic Third-Harmonic Generation of a Laser in a Self-Sustained Magnetized Plasma Channel

Relativistic third-harmonics of a laser in a magnetized plasma channel is studied. Due to relativistic self-focusing in plasma, a high-intensity laser pulse pushes the plasma electrons radially outward to create a plasma channel. The relativistic mass effect and the magnetic field contribute to the nonlinear dielectric response of plasma and create a plasma channel due to the laser self-focusing. Self-sustained plasma channel is very important and may affect the efficiency of harmonic generation of the interacting laser beam. The velocity and density perturbation associated with the self-focused laser beam can generate a nonlinear current at triple fold frequency of the fundamental laser. Our results show the significant effect of the self-sustained magnetized plasma channel on the efficiency of third-harmonic generation of the laser beam.