Thermal nonlinearity and small-scale stratification in a magnetized plasma showing coulomb collisions in a high-frequency field

A magnetized plasma having Coulomb collisions in a strong high-frequency field behaves as a nonlinear medium having a new thermal nonlinearity mechanism due to the transverse thermal driving force affecting the transport. This is due to thermal diffusion transverse to the magnetic field, so the charged-particle concentration in the field-heated region increases, not decreases, as is the case in other thermal-nonlinearity mechanisms. The quasistatic instability in such a plasma has been examined for the case where the electric-field vector is perpendicular to the external magnetic field. Threshold fields have been determined for instability, together with maximum increments and wave numbers for the most rapidly growing perturbations. A qualitative study is made on the stationary structures in the nonlinear plasma formations. This instability is used in a proposed mechanism for small-scale stratification in the ionospheric plasma in a strong radio wave.