Self-focusing of a whistler propagating at an angle to the magnetic field in a plasma

Abstract

The self-focusing of a low-frequency whistler wave, propagating at an angle to the ambient magnetic field in a plasma, is studied. The nonlinearity arises due to the pondermotive force on electrons and subsequent redistribution of plasma along the magnetic field. The direction of self-focusing differs from that of phase propagation due to plasma anisotropy. In the three-dimensional (3D) case, the self-focusing is sharper and increases as θ increases.In the 2D slab model, self-focusing occurs with spatial periodicity.