Sum and Difference Frequency Generation in a Plasma by Two Nonuniform Electric Fields in the Presence of a Static Magnetic Field. II

Abstract

Boltzmann equation analysis is made of nonlinear generation of sum and difference frequency components in a current density, due to two rf electric field applied to a magneto-plasma. Mechanism of the nonlinearity lies in nonuniform nature of the rf electric fields. All the related frequencies are assumed to be sufficiently high that dynamics of ions can be ignored. A general expression of the current density is derived both in slightly and fully ionized plasmas. Under suitable conditions, the general expression reduces to what was derived earlier by several authors. Numerical results show; (a) the nonlinear current depends much on a velocity dependence of collision frequency and (b) difference between collision frequencies ν_l’s (l=1, 2) cannot be ignored. Electron-electron collision does not contribute to the nonlinear current in a magneto-plasma as in unmagnetized plasma treated by Shkarofsky. Vanishing of the contribution from the e-e collision is due to a fortuitous cancellation of the contributions from linear and nonlinear collision terms.