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Updated: Jul 11, 2026
10:21
Evanescent Field Based Photoacoustics: Optical Property Evaluation at Surfaces
Published on: July 26, 2016
Diffraction of evanescent plane waves by a resistive half-plane
1Cankaya University, Engineering Faculty, Electronic and Communication Department, Balgat-Ankara, Turkey. yziya@cankaya.edu.tr
Summary
This study examines evanescent plane wave diffraction using a modified physical optics theory. Numerical plots reveal how incident field parameters affect scattered evanescent waves.
Area of Science:
- Electromagnetics and Wave Propagation
- Optics and Photonics
Background:
- Evanescent waves are critical in near-field optics and surface plasmon resonance.
- Diffraction phenomena are fundamental to understanding wave behavior at boundaries.
Purpose of the Study:
- To analyze the diffraction of evanescent plane waves by a resistive half-plane.
- To develop a uniform evaluation method for scattering integrals.
Main Methods:
- Utilized the modified theory of physical optics to construct scattering integrals.
- Employed an unusual uniform evaluation technique for these integrals.
- Obtained scattered fields by assigning complex values to the angle of incidence.
Main Results:
- Successfully derived expressions for the scattered fields of evanescent waves.
- Numerically plotted the behavior of diffracted waves for varying incident field parameters.
- Demonstrated a method for uniform asymptotic evaluation of scattering integrals.
Conclusions:
- The study provides a novel approach to analyzing evanescent wave diffraction.
- The numerical results offer insights into the interaction of evanescent waves with resistive surfaces.
- This method is applicable to other wave diffraction problems involving complex angles of incidence.
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