Abstract

Subwavelength focusing in mesoscale structures was measured in the near field. Specifically, we found that plane waves form focused beams in higher topographic regions when they propagate through mesoscale transparent air–dielectric structures. By finite-difference time-domain simulations we verified that light diffracted off topographic edges and its convergence at higher topographic regions are the mechanisms for focus. This subwavelength focusing effect provides a simple way for mass production of mesoscale periodic structures. We made subwavelength gratings and hole arrays to demonstrate their feasibility.

© 2004 Optical Society of America

Diffraction-induced near-field optical images in mesoscale air–dielectric structures

Pei-Kuen Wei, Hsieh-Li Chou, and Wei-Lun Chang
J. Opt. Soc. Am. B 20(7) 1503-1507 (2003)

Characterization of the signature of subwavelength variation from far-field irradiance

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Subwavelength focusing and imaging by a multimode optical waveguide

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Sub-wavelength patterning of the optical near-field

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Opt. Express 12(2) 282-287 (2004)

Near-field effects of focused illumination on periodic structures in scanning tunneling optical microscopy

Fadi I. Baida, Dominique Barchiesi, and Daniel Van Labeke
Opt. Lett. 24(22) 1587-1589 (1999)