Extension of the general thermal field equation for nanosized emitters
Abstract
During the previous decade, Jensen et al. developed a general analytical model that successfully describes electron emission from metals both in the field and thermionic regimes, as well as in the transition region. In that development, the standard image corrected triangular potential barrier was used. This barrier model is valid only for planar surfaces and therefore cannot be used in general for modern nanometric emitters. In a recent publication, the authors showed that the standard FowlerNordheim theory can be generalized for highly curved emitters if a quadratic term is included to the potential model. In this paper, we extend this generalization for high temperatures and include both the thermal and intermediate regimes. This is achieved by applying the general method developed by Jensen to the quadratic barrier model of our previous publication. We obtain results that are in good agreement with fully numerical calculations for radii R > 4 nm, while our calculated current density differs by a factor up to 27 from the one predicted by the Jensen's standard GeneralThermalField (GTF) equation. Our extended GTF equation has application to modern sharp electron sources, beam simulation models, and vacuum breakdown theory.
 Authors:
 Department of Electrical and Computer Engineering, National Technical University of Athens, Zografou Campus, Athens 15700 (Greece)
 Publication Date:
 OSTI Identifier:
 22494957
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Applied Physics; Journal Volume: 119; Journal Issue: 4; Other Information: (c) 2016 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; CURRENT DENSITY; ELECTRON EMISSION; ELECTRON SOURCES; FIELD EQUATIONS; FOWLERNORDHEIM THEORY; METALS; NANOSTRUCTURES
Citation Formats
Kyritsakis, A., Email: akyritsos1@gmail.com, and Xanthakis, J. P. Extension of the general thermal field equation for nanosized emitters. United States: N. p., 2016.
Web. doi:10.1063/1.4940721.
Kyritsakis, A., Email: akyritsos1@gmail.com, & Xanthakis, J. P. Extension of the general thermal field equation for nanosized emitters. United States. doi:10.1063/1.4940721.
Kyritsakis, A., Email: akyritsos1@gmail.com, and Xanthakis, J. P. Thu .
"Extension of the general thermal field equation for nanosized emitters". United States.
doi:10.1063/1.4940721.
@article{osti_22494957,
title = {Extension of the general thermal field equation for nanosized emitters},
author = {Kyritsakis, A., Email: akyritsos1@gmail.com and Xanthakis, J. P.},
abstractNote = {During the previous decade, Jensen et al. developed a general analytical model that successfully describes electron emission from metals both in the field and thermionic regimes, as well as in the transition region. In that development, the standard image corrected triangular potential barrier was used. This barrier model is valid only for planar surfaces and therefore cannot be used in general for modern nanometric emitters. In a recent publication, the authors showed that the standard FowlerNordheim theory can be generalized for highly curved emitters if a quadratic term is included to the potential model. In this paper, we extend this generalization for high temperatures and include both the thermal and intermediate regimes. This is achieved by applying the general method developed by Jensen to the quadratic barrier model of our previous publication. We obtain results that are in good agreement with fully numerical calculations for radii R > 4 nm, while our calculated current density differs by a factor up to 27 from the one predicted by the Jensen's standard GeneralThermalField (GTF) equation. Our extended GTF equation has application to modern sharp electron sources, beam simulation models, and vacuum breakdown theory.},
doi = {10.1063/1.4940721},
journal = {Journal of Applied Physics},
number = 4,
volume = 119,
place = {United States},
year = {Thu Jan 28 00:00:00 EST 2016},
month = {Thu Jan 28 00:00:00 EST 2016}
}

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