Title :
Emittance and emission from arrays with statistical variation
Author :
Petillo, John ; Panagos, Dimitrios N. ; Jensen, Kevin L.
Author_Institution :
Sci. Applic. Int. Corp., Billerica, MA, USA
Abstract :
We report on the incorporation of a model of field emitters based on a Point Charge Model (PCM) that allows for rapid and analytical representations of tip current, variation, and emission statistics and its implementation and usage in the MICHELLE Particle-In-Cell (PIC) code to model the impact of emission variation on current characteristics and emittance. Rather than cold field emission characterized by the Fowler Nordheim equation, a General Thermal-Field (GTF) emission model treats warm and hot field emission sources. We shall compare the increases in emittance and beam radius due to emission non-uniformity as modeled by assuming a Log-Normal (LN) distribution of emitter geometries. The consequences for high frequency devices shall be explored.
Keywords :
emission; field emitter arrays; log normal distribution; statistical analysis; Fowler Nordheim equation; GTF emission; MICHELLE particle-in-cell; PCM; PIC code; cold field emission; emission statistics; field emitters; general thermal-field emission; log-normal distribution; point charge model; statistical variation; Analytical models; Cathodes; Current density; Mathematical model; Phase change materials; Space charge; Trajectory;
Conference_Titel :
Vacuum Electronics Conference (IVEC), 2013 IEEE 14th International
Conference_Location :
Paris
Print_ISBN :
978-1-4673-5976-4
DOI :
10.1109/IVEC.2013.6571148
