Molecular Dynamics Simulations of Mutual Space-Charge Effect between Planar Field Emitters

TL;DR

This paper uses molecular dynamics simulations to study how space-charge effects influence electron emission from multiple planar emitters, revealing that emitter spacing significantly impacts their mutual interactions.

Contribution

It introduces a detailed simulation approach to analyze mutual space-charge effects between multiple planar emitters with full Coulomb interactions.

Findings

Emitters are independent when spaced more than half the gap distance.

Mutual space-charge effects increase rapidly at smaller spacings.

A qualitative explanation for the observed effects is provided.

Abstract

Molecular dynamics simulations, with full Coulomb interaction and self-consistent field emission, are used to examine mutual space-charge interactions between beams originating from several emitter areas, in a planar infinite diode. The simulations allow observation of the trajectory of each individual electron through the diode gap. Results show that when the center-to-center spacing between emitters is greater than half of the gap spacing the emitters are essentially independent. For smaller spacing the mutual space-charge effect increases rapidly and should not be discounted. A simple qualitative explanation for this effect is given.