I gather this thing ionizes air to create a positively charged "working fluid" which accelerates away from the anode in a cone shaped pattern. The working fluid doesn't generate [much(?)] thrust directly, as it collides with the craft again at the cathode. But along the way some of the ions near the edge of the cone bump into and accelerate neutral air molecules, generating the [bulk of the(?)] thrust that propels the craft.

With a modified design, is it possible to accelerate the ionized air so fast that all of it vents out the exhaust (e.g. using magnets)? Would that result in higher efficiency / higher thrust? Are there already atmosphere-breathing engines that do this and what are they called?