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Updated: Jul 9, 2026
06:58
Electrochemical Etching and Characterization of Sharp Field Emission Points for Electron Impact Ionization
Published on: July 12, 2016
Summary
Evanescent waves, crucial in near-field optics, do not physically contribute to source radiation fields or scatterer far fields, despite recent claims. This study clarifies their limited physical consequences.
Area of Science:
- Optics and Photonics
- Electromagnetism
- Near-field phenomena
Background:
- Evanescent waves are of significant interest due to advances in near-field optics.
- Previous claims suggested evanescent waves contribute to radiation fields of sources and far fields of scatterers.
Purpose of the Study:
- To investigate and clarify the physical contribution of evanescent waves to radiation and far fields.
- To address and correct misleading claims regarding evanescent wave influence in optics.
Main Methods:
- Analysis of a spherical scalar wave.
- Examination of a linear electric dipole field.
- Theoretical evaluation of wave field contributions.
Main Results:
- Evanescent wave contributions to source radiation fields are shown to be misleading.
- Evanescent wave contributions to scatterer far fields are demonstrated to be without physical consequence.
- The findings are applicable to a wide range of electromagnetic fields.
Conclusions:
- Evanescent waves do not physically impact the radiation fields of sources or the far fields of scatterers.
- The physical consequences of evanescent wave contributions are negligible.
- This work provides a foundational understanding for near-field optics and electromagnetism.
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