Scattering of a linearly polarised electromagnetic wave of relativistic intensity in matter (one-dimensional theory)

A one-dimensional model framework is used in a rigorous linear analysis of an instability of a linearly polarised electromagnetic wave of relativistic intensity. It is shown that, in a plasma, this wave is not monochromatic but represents a flux of photons with frequencies shifted by a multiple of the plasma frequency. In the relativistic intensity range an instability gives rise to Raman scattering by plasmons. The centre of the gain line for a specific harmonic is influenced by a hydrodynamic analogue of the Compton effect, the far wings of the gain line are the results of generation of the Langmuir noise, and the gain line profile depends on the intensity of a reference wave.