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Title: Broadband Forward Light Scattering by Architectural Design of Core–Shell Silicon Particles
Abstract

A goal in the field of nanoscale optics is the fabrication of nanostructures with strong directional light scattering at visible frequencies. Here, the synthesis of Mie‐resonant core–shell particles with overlapping electric and magnetic dipole resonances in the visible spectrum is demonstrated. The core consists of silicon surrounded by a lower index silicon oxynitride (SiOxNy) shell of an adjustable thickness. Optical spectroscopies coupled to Mie theory calculations give the first experimental evidence that the relative position and intensity of the magnetic and electric dipole resonances are tuned by changing the core–shell architecture. Specifically, coating a high‐index particle with a low‐index shell coalesces the dipoles, while maintaining a high scattering efficiency, thus generating broadband forward scattering. This synthetic strategy opens a route toward metamaterial fabrication with unprecedented control over visible light manipulation.

 
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Award ID(s):
2001650 1720595
NSF-PAR ID:
10361690
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Advanced Functional Materials
Volume:
31
Issue:
26
ISSN:
1616-301X
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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