Parametric decay of a high-power helicon wave into a transverse acoustic and another helicon waves in longitudinally magnetised cubic piezoelectric semiconducting plasmas

A detailed analytical investigation is made of the parametric decay of a high-power helicon into another helicon and an acoustic wave in a longitudinally magnetised n-type cubic piezoelectric semiconducting crystal belonging to the class 4-bar3m. The dispersion relation is obtained by using a hydrodynamic model of an homogeneous, piezoelectric, one-component (electron) semiconducting plasma, and the threshold value of pump electric field and the growth rate of unstable mode well above the threshold are discussed. The analysis is applied to a specific semiconductor, n-InSb at 77 K duly irradiated by a high-power helicon wave for numerical estimation. The laser wave intensities used are in the range of 109 to 1012 Wm-2 which is assumed to be less than the damage threshold of the InSb crystal. The order of wave amplitude is feasible presently. The growth rate is found to be of the order of 1010 s-1. (author)