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Title: Anomalous reflection for highly efficient subwavelength light concentration and extraction with photonic funnels
Abstract Photonic funnels, microscale conical waveguides that have been recently realized in the mid-IR spectral range with the help of an all-semiconductor designer metal material platform, are promising devices for efficient coupling of light between the nanoscales and macroscales. Previous analyses of photonic funnels have focused on structures with highly conductive claddings. Here, we analyze the performance of funnels with and without cladding, as a function of material properties, operating wavelength, and geometry. We demonstrate that bare (cladding-free) funnels enable orders-of-magnitude higher enhancement of local intensity than their clad counterparts, with virtually no loss of confinement, and relate this phenomenon to anomalous reflection of light at the anisotropic material–air interface. Intensity enhancement of the order of 25, with confinement of light to wavelength/20 scale, is demonstrated. Efficient extraction of light from nanoscale areas is predicted.  more » « less
Award ID(s):
2004298 2004422
PAR ID:
10552021
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
DeGruyter
Date Published:
Journal Name:
Nanophotonics
ISSN:
2192-8606
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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