Ion Thermal Rogue Waves Behaviour in Pure Pair-Ion Plasma

The properties of ion thermal rogue waves in unmagnified warm pair-ion plasma in the vicinity of the critical density of the negative ions are investigated. Using the reductive perturbation theory, an extended modified Korteweg-de Vries equation (EMKdV) is obtained. At small wave number and using the derivative expansion method the EMKdV equation is reduced to the corresponding nonlinear Schrödinger equation (NLSE). In the regions of the modulation instability, rogue waves are formed. It is found that the different system parameters have remarkable effects on both the possibility of forming the rogue waves as well as their amplitudes.