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Updated: Nov 6, 2025
06:58
Electrochemical Etching and Characterization of Sharp Field Emission Points for Electron Impact Ionization
Published on: July 12, 2016
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The pre-exponential voltage-exponent as a sensitive test parameter for field emission theories.
R G Forbes1, E O Popov2, A G Kolosko2
1Advanced Technology Institute and Department of Electrical and Electronic Engineering, University of Surrey, Guildford, Surrey GU2 7XH, UK.
Royal Society Open Science
|May 7, 2021
Summary
Comparing theoretical and experimental k-values in field electron emission (FE) provides a sensitive tool for validating FE theories. This method aids in selecting between competing theories by analyzing current-voltage data.
Area of Science:
- Physics
- Materials Science
- Surface Science
Background:
- Field electron emission (FE) follows an empirical equation: I_m = CV_m^k exp[-B/V_m].
- Extracting the exponent k is crucial for understanding FE behavior.
- k-values can be derived from simulations or high-quality experimental current-voltage (I-V) measurements.
Purpose of the Study:
- To establish a method for comparing theoretically derived and experimentally derived k-values in FE.
- To demonstrate the utility of k-value comparison for validating FE theories and distinguishing between them.
- To summarize existing knowledge and methods for k-value extraction.
Main Methods:
- Discussion of existing methods for extracting k-values from experimental and simulated I-V data.
- Introduction of a modernized 'least residual' method for k-value extraction.
- Reporting of exploratory simulations to test the k-value extraction methodology.
Main Results:
- The comparison of theoretical and experimental k-values serves as a sensitive tool for FE theory assessment.
- Extracted k-values reliably match independently known analytical results.
- Extracted k-values are sensitive to specific emission theories and assumed emitter shapes.
Conclusions:
- Comparing theoretical and experimental k-values offers a robust approach for validating FE theories.
- Future research should focus on disentangling the influence of emission theory and emitter shape on k-values.
- This methodology can help investigate various scientific issues in field electron emission.
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