Nonlinear oblique modulation of ion-acoustic waves in a two warm ion plasma

Using the KBM perturbation technique, the stability of oblique modulation on ion-acoustic waves in a plasma with two species of warm ions is studied. The effect of the temperatures of two ion species on the modulational instability is discussed in detail. The nonlinear frequency shift and the change in zeroth-order density are also calculated for different values of ion temperatures. Predictions of the theory are in fairly good agreement with the experimental observation of modulational instability.