Nonlinear oscillations and waves in an arbitrary mass ratio cold plasma

It is well known that nonlinear standing oscillations in an arbitrary mass ratio cold plasma always phase mix away. However, there exist nonlinear electron-ion traveling wave solutions, which do not exhibit phase mixing because they have zero ponderomotive force. The existence of these waves has been demonstrated using a perturbation method. Moreover, it is shown that cold plasma BGK waves [Albritton , Nucl. Fusion 15, 1199 (1975)] phase mix away if ions are allowed to move and the scaling of phase mixing is found to be different from earlier work [Sengupta , Phys. Rev. Lett. 82, 1867 (1999)]. Phase mixing of these waves has been further verified in 1-D particle in cell simulation. (C) 2011 American Institute of Physics. [doi:10.1063/1.3672517]