Generation of a quasistationary magnetic field by a high-frequency wave

A new effect, specifically, generation of a quasistationary magnetic field (QMF) in weaklly collisional plasma in a spatially nonuniform high-frequency field of the whistler frequency range, was discovered in the experiments at the large-scale plasma KROT setup. QMP sources are nonlinear currents excited by the parallel and perpendicular components of the ponderomotive force that affects charged particles motion in the spatially localized high-frequency pump field.

The dynamics of the excited magnetic field and quasistationary currents has been studied, and the time of QMF has been found to depend on the turn-on time of the high-frequency field. Pulse currents and magnetic fields are carried out of their generation zones at the velocity of low-frequency whistlers. This effect can be used to generate low-frequency waves in active ionospheric experiments. This research was supported by the Russian Foundation for Basic Research (project No. 10-02-01417-а.

Geometry of the nonlinear drift current excited in the pump beam

High-frequency pump pulse (a), nonintegrated signal from B-dot probe (b), and the shape of the QMF pulse and the plasma density disturbance detected simultaneously (c)

Aidakina N. A., Gushchin M. E., Zudin I. Yu., Korobkov S. V., Kostrov A. V., and Strikovskii A. V. Quasistationary magnetic field generated in a plasma by a whistler-mode radio pulse // JETP Letters, 2011, V. 93, No. 9, P. 498–502.