Nonlinear Interaction of Light in a Plasma

Abstract

The elastic scattering of light off light in the presence of a plasma is investigated. The cross section for this process is expressed in terms of matrix elements of the charge-density operator between exact eigenstates of the many-body system (plasma). The cross section is evaluated to the lowest order in the plasma parameter $r_s\equiv {\left(\frac{n}{{q_d}^3}\right)}^{-1\mathrm{}}$. A study of the dependence of the differential cross section on momentum and energy transferred in the scattering will allow one to measure the plasma dielectric functions. Although the cross sections are small, the development of intense light sources (lasers) makes a measurement feasible.