Electron-Hole Disruption due to Ion Motion and Formation of Coupled Electron Hole and Ion-Acoustic Soliton in a Plasma

A computer simulation reveals that an electron phase-space hole whose velocity is of the order of or slower than the ion-acoustic speed strongly interacts with ions in a collisionless plasma. The ion motion leads to the disruption of an electron hole into two holes, and forms new coupled states of electron holes and ion-acoustic solitons. This dynamics can be explained by a theory using Sagdeev's potential. In the case of a bigger hole, it is entirely broken into many small holes.