Generation of a poloidal magnetic field in a noncollisional plasma by an elliptically polarized Gaussian laser beam

Abstract

The generation of poloidal magnetic field in an inhomogeneous cold, collisionless plasma by an elliptically polarized Gaussian laser beam is discussed. A field in the range of megagauss is induced by the laser inhomogeneity effect even for a normal incident beam. This field scales as I0 λ, where I0 and λ are the intensity and wavelength of the laser beam, respectively, and is independent of the density profile structure. The small angular correction factor due to focal spot asymmetry scales as ∼I0λ3 and may be significant for a small-sized plasma with a steep density profile. The limitation of our model is discussed, with possible implications.