There is interest in the use of carbon nanotubes (CNTs) to create a field emission cathode. The primary benefit of this cathode is that a gas flow is not required to create electrons, which is of critical importance for space missions that must minimize propellant mass. A field emission cathode consisting of CNT arrays is fabricated by the Georgia Tech Research Institute and the Georgia Tech Hi...

Charge neutralization of an In-FEEP thruster was demonstrated with three different electron sources by zeroing the floating potential of the thruster and neutralizer system. The three cathodes used in the investigation include a mixed metal thermionic cathode, a carbon nanotube field emission cathode, and a Spindt-type Mo field emission array cathode. The field emission cathodes significantly i...

An integrated theoretical model has been developed to predict the entire range of emission from thermionic to field emission, including the mixed emission regime. The model assumes a Sommerfeld free electron model supply function, for which the Fermi-Dirac distribution applies with a nonzero temperature. The electron transmission coefficient is calculated in one dimension using a transfer matri...

In the current report, chemically synthesized copper phthalocyanine (CuPc) nanotubes are shown to exhibit unprecedentedly well cold cathode emission characteristics with turn-on field (3.2 V μ m(-1)) and stable emission during long intervals (200 min). Simulation of electric field distribution via finite element method around an isolated nanotube emitter in a manner parallel to the experimental...

Field emission is one of the principal phenomena limiting the operating voltage of practical electron guns. There is interest in developing photoemission cathode based DC electron guns employing cathode field strengths and cathode-anode voltages well above the present stateof-the-art. Such electron sources could provide high brightness, high average current beams for energy recovered supercondu...

During Phase I, the following goals were achieved: (1) design and fabrication of a novel, nano-dimensional CNT field emitter assembly for high current density application, with high durability; (2) fabrication of a ceramic based micro channel plate (MCP) and characterization of its secondary electron emission; and (3) characterizing the CNT/MCP cathode for high field emission and durability. As...