Simulation of using background plasma to neutralize charged particle thrusters on nanospacecraft

There is an emerging class of nanospacecraft thrusters under development that use colloids or nanoparticles that can be charged either positively or negatively to provide thrust. An issue to be examined is how to adequately neutralize both the spacecraft and the emitted beam. We initially focused on the capabilities of the nanoparticle field extraction thruster (NanoFET) to self-neutralize (although it applies to colloidal systems as well). The NanoFET system operates by expelling either positively or negatively charged nanoparticles through a gridded structure. This ability to charge nanoparticles to either polarity offers the flexibility to also use the nanoparticles to neutralize the system, which has been previously examined. Most common electric propulsion systems only emit positively-charged ions, which requires that electrons are also emitted, often through the use of hollow cathodes or other electron emitters. These neutralization techniques all reduce efficiency. If NanoFET did not need a separate system to be neutralized, then there would be no loss of efficiency.