Toroidally rotating plasma confinement with a spatially periodic field

Some possible plasma confinement configurations are identified in which a spatially periodic electrostatic or magnetostatic field may provide or enhance ion confinement. The plasma drifts at a speed much faster than the ion thermal speed. The periodic field has a spatial period that is much smaller than the plasma size, and the field has a non-negligible strength only at the plasma edge. The periodic field could be produced, for example, by a sequence of electrodes with alternating applied voltages or a sequence of wires with alternating current directions. Classical trajectory Monte Carlo simulation results are used to develop expressions for predicting the conditions under which ions are reflected away from an artificially structured boundary that produces a spatially periodic field, without the ions reaching the boundary.