Amplitude modulation of three-dimensional low-frequency solitary waves in a magnetized dusty superthermal plasma

The amplitude modulation of three-dimensional (3d) dust ion-acoustic wave (diaw) packets is studied in a collisionless magnetized plasma with inertial positive ions,superthermal electrons and negatively charged immobile dust grains. by using the reductive perturbation technique,a 3d-nonlinear schrödinger equation is derived,which governs the slow modulation of diaw packets. the latter are found to be stable in the low-frequency (ω< ωc) regime,whereas they are unstable for ω> ωc,and the modulational instability is related to the modulational obliqueness (θ). here,ω(ωc) is the nondimensional wave (ion-cyclotron) frequency. it is shown that the superthermal parameter κ,the frequency ωc as well as the charged dust impurity (0 < μ< 1) shift the mi domains around the plane,where μ is the ratio of electron-to-ion number densities. furthermore,it is found that the decay rate of instability is quenched by the superthermal parameter κ with cutoffs at lower wave number of modulation (k); however,it can be higher (lower) with increasing values of μ(ωc) having cutoffs at higher values of k. © 2017,the author(s).