POLARIZATION OF THE HIGH HARMONICS OF RADIATION IN A LASER-PLASMA

The polarization of the high harmonics generated in plasmas by the bre msstrahlung of electrons oscillating under the influence of high power plasma-heating electromagnetic radiation is described on the basis of a simple model of a cold plasma. It is shown that when the polarizati on of the heating radiation differs from plane polarization by a small but finite amount, the high harmonics are generated with almost perpe ndicular polarization, and the degree of circular polarization of the harmonics increases with the number of the harmonic. (C) 1998 American Institute of Physics. [S0021-3640(98)00505-2].