The devices may find use in other space- and earth-borne applications requiring low-power, cold electron emission in environments that would be hostile to traditional Spindt-type emission cathode. Re-generable field emitters could be used in electron microscopy, electron beam lithography, flat-panel video displays, etc.
The proposed neutralization technique would be especially well suited (but not limited) to use in FEEP systems, where the FEEP ion emitters can be re-purposed as electron emitters for spacecraft neutralization. In this arrangement two identical FEEP thrusters could share duties, with one performing neutralization and the other ion emission swapping roles when the electron field-emitters need to be re-generated, and greatly reducing system complexity. Furthermore, the architectural similarity between FEEP thrusters and the proposed neutralizer technique could enable a unique hybrid system: an array of emitters could be operated in electron-emission mode as the neutralizer for a meso-scale Hall or ion thruster during portions of a mission requiring high thrust-to-power, then switched over to ion-emission mode to function independently as a FEEP thruster when high Isp is desired.
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