Particle-in-cell simulations of an inverted sheath

An inverted sheath is simulated by particle-in-cell simulations using the XPDP1 code. It is shown that a stable monotonically decreasing potential structure can be formed in a bounded plasma system, where positive ions and source electrons are injected from the right-hand side (source) electrode and emitted electrons are injected from the left-hand side (collector) electrode. Such inverted sheath structure is created in the absence of collisions or ionization, provided that the ratio of injection fluxes of both electron groups is large enough. In this work preliminary results are reported and some effects of different ion injection are illustrated.