Nonlinear interaction of electromagnetic waves in a dense plasma

We discuss the nonlinear phenomena caused by the quadratic interaction of electromagnetic waves in a dense charged medium (Coulomb systems and plasma), including the parametric generation and second harmonic generation of the electromagnetic radiation. To determine the quadratic reaction functions describing the interaction of electromagnetic waves in a medium, an approach based on the explicit approximations for the reaction functions with adjustable parameters is used. The parameters are found from the exact frequency moments of the reaction functions. Using the data on the reaction functions, the conditions for the experimental implementation of the above-mentioned phenomena in a laboratory dense plasma in a dc magnetic field are estimated.