Subdiffraction Focusing Enabled by a Fano Resonance
Date
2014-08-01
Authors
Chen, Shuwen
Jin, Shilong
Gordon, Reuven
Journal Title
Journal ISSN
Volume Title
Publisher
Physical Review X
Abstract
Radiationless electromagnetic interference (REI) has been used to achieve focusing below Abbe’s diffraction limit. Here, we demonstrate an approach to REI that uses the Fano resonance of subwavelength slits to achieve subdiffraction focusing. Two main features of the Fano resonance are critical: (1) The Fano resonance suppresses radiation by destructive interference, thereby allowing for REI, and (2) the Fano resonance creates a resonant field enhancement allowing one to overcome evanescent decay, which is different from past approaches to REI. An analytic theory is introduced to explain these results. While the analytic theory is formulated for a perfect electric conductor, comprehensive numerical simulations show the applicability in the visible regime, where losses and plasmonic effects play a role.
Description
Keywords
Nanophysics, Optics, Plasmonics
Citation
Chen, S., Jin, S. & Gordon, R. (2014). Subdiffraction focusing enabled by a fano resonance. Physical Review X, 4(031021), 1-8.