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Electrochemical Etching and Characterization of Sharp Field Emission Points for Electron Impact Ionization
Published on: July 12, 2016
The transverse structure of cold field electron emission
1Department of Physics, University of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE, UK. cje1@cam.ac.uk
Ultramicroscopy
|September 25, 2010
Summary
Electron emission from electrodes is modeled using Schrödinger
Area of Science:
- Quantum mechanics
- Solid-state physics
- Electron emission phenomena
Background:
- Understanding electron emission is crucial for vacuum electronics and semiconductor devices.
- Previous models often simplified the complex quantum mechanical behavior of electrons.
- Investigating electron behavior in uniform electric fields is a fundamental problem.
Purpose of the Study:
- To solve the Schrödinger equation for electron emission from a localized area between planar electrodes.
- To analyze the effect of transverse momentum on electron tunneling through potential barriers.
- To characterize the spatial distribution and intensity of the emitted electron beam.
Main Methods:
- Numerical solution of the Schrödinger equation for a multi-dimensional system.
- Analysis of electron wave function behavior in a uniform electric field.
- Modeling electron emission from a point source and a small area.
Main Results:
- Wave components with transverse momentum experience modified potential barrier height and width.
- The electron beam intensity exhibits a Gaussian decrease with increasing beam radius.
- A characteristic Gaussian radius was found to increase with the square root of the distance from the emission plane.
Conclusions:
- Transverse momentum significantly influences electron tunneling and beam characteristics.
- The spatial spread of the electron beam is dependent on the electric field configuration.
- These findings have implications for designing electron sources and understanding electron transport in vacuum devices.
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