Threshold characteristics of the surface-kink instability of a semiconductor plasma in a germanium plate

Abstract

Experimental results on the relationship between the threshold electric and magnetic fields (the threshold curve) for the surface-kink instability are discussed. Experimental results on the dependence of the threshold oscillation frequency on the electric field E in n-and p-type germanium plates are discussed for the case in which the length and width of the plates are much greater than their thickness d, and d is shorter than the charge-carrier diffusion length. Analysis of the voltage-current characteristics and of the threshold curves shows that the surface-kink instability occurs in a weakly injected plasma at 78 and 300°K. When this circumstance is taken into account, the general theory of the surface-kink instability for the cases n ≠ p and un ≠ μp gives a satisfactory description of the threshold curves and of the E dependence of the threshold frequency. It is concluded that improving the agreement of theory with experiment will require allowing for the nonuniformity of the distribution of the semiconductor plasma along the axis along which the electric and magnetic fields are directed.