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Local Imaging of Photonic Structures: Image Contrast From Impedance Mismatch
Published
Author(s)
A L. Campillo, Julia W. Hsu, Garnett W. Bryant
Abstract
Photonic structures constructed from square arrays of air holes in Si3Nx membranes are locally imaged by near-field optical microscopy in illumination mode. Holes with diameters smaller than and larger than the wavelength of light are investigated. Counterintuitively, the holes appear dark and the film is bright in transmission images for both hole sizes. Modeling shows that the dominant contrast mechanism is enhanced light emission from the tip when the tip is above the film. Tip emission is enhanced because the tip-air impedance mismatch is reduced when the tip is above the high-index film.
Citation
Optics Letters
Volume
27
Issue
No. 6
Pub Type
Journals
Keywords
near-field optical microscopy, photonics, SiN
Citation
Campillo, A.
, Hsu, J.
and Bryant, G.
(2002),
Local Imaging of Photonic Structures: Image Contrast From Impedance Mismatch, Optics Letters
(Accessed October 10, 2025)