Spatially shifted beam approach to subwavelength focusing.
Although negative-refractive-index metamaterials have successfully achieved subwavelength focusing, image resolution is limited by the presence of losses. In this Letter, a metal transmission screen with subwavelength spaced slots is proposed that focuses the near-field beyond the diffraction limit and, furthermore, is easily scaled from microwave frequencies to the optical regime. An analytical model based on the superposition of shifted-beam patterns is developed that agrees very well with full-wave simulations and is corroborated by experimental results at microwave frequencies.
The Edward S. Rogers Sr. Department of Electrical and Computer Engineering, University of Toronto, 40 St. George Street, Toronto, Ontario, M5S 2E4, Canada.
Loïc
L
Markley
Alex M H
AM
Wong
Yan
Y
Wang
George V
GV
Eleftheriades