Global nonambipolar flow: Plasma confinement where all electrons are lost to one boundary and all positive ions to another boundary

A new mode of plasma confinement is demonstrated in which essentially all positive ions leave the plasma to only one boundary while essentially all electrons are lost to a different boundary. Sheaths near the plasma boundaries are entirely responsible for this global nonambipolar flow. The bulk plasma remains quasineutral and unperturbed even when all electrons are lost to only one, physically small, location. A necessary condition for global nonambipolar flow depends on the ratio of electron collection area to ion collection area. The plasma electron temperature is significantly higher in the global nonambipolar mode than in the typical ambipolar mode due to a relative increase in confinement of high-energy electrons and a relative decrease in confinement of low-energy electrons. (c) 2007 American Institute of Physics.