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Updated: Jun 22, 2026

Evanescent Field Based Photoacoustics: Optical Property Evaluation at Surfaces
Published on: July 26, 2016
Simple demonstration of visible evanescent-wave enhancement with far-field detection
Emily A Ray1, Meredith J Hampton, Rene Lopez
1Department of Physics and Astronomy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA. earay@physics.unc.edu
Abstract:
We demonstrate the fabrication of a simple metamaterial-diffraction grating device that both amplifies and converts evanescent waves into propagating ones. This is the most accessible example of such phenomena reported until now (to our knowledge), as it requires few thin film layers, operates in the visible, and can be probed with traditional optics. The metamaterial exhibits amplification of evanescent waves generated from total internal reflection. The device was fabricated over 1 cm2 using pulsed-laser deposition and a pattern-replication technique.
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