An asymmetric plasma divided by a magnetic filter is numerically simulated by the one-dimensional particle-in-cell code VSIM1D ͓Koga et al., J. Phys. Soc. Jpn. 68, 1578 ͑1999͔͒. Depending on the asymmetry, the system behavior is static or dynamic. In the static state, the potentials of the main plasma and the subplasma are given by the sheath potentials, M ϳ3T Me /e and S ϳ3T Se /e, respectively, with e being an electron charge and T Me and T Se being electron temperatures (T Me ϾT Se ). In the dynamic state, while M ϳ3T Me /e, S oscillates periodically between S,min ϳ3T Se /e and S,max ϳ3T Me /e. The ions accelerated by the time varying potential gap get into the subplasma and excite the laminar shock waves. The period of the limit cycle is determined by the transit time of the shock wave structure.