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Updated: Sep 27, 2026

Determination of the Excitation and Coupling Rates Between Light Emitters and Surface Plasmon Polaritons
Published on: July 21, 2018
Fowler-Nordheim theory for a spherical emitting surface
1Cavendish Laboratory, University of Cambridge, Madingley Road, CB3 0HE, Cambridge, UK. cje1@cam.ac.uk
Abstract:
In tests on a field emitter whose dimensions and work function were known, Fowler-Nordheim (F-N) theory as usually stated for a planar emitter was found to give poor agreement with observations. The effect of curvature of the emitting surface has been modelled by including (a) non-linear variation of potential with distance from the surface; (b) the consequent changes in the exponent and pre-exponential terms in the F-N expression for current; and (c) the variation of current density over the surface, modelled by an effective solid angle. Application of the resulting expression to the measured data gives estimates for apex radius which agree much more closely with the measured value than the value from planar theory does.
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