Resonant Scattering of Light from Dielectric Nanopillars

The use of plasmonic nanoparticles dispersed in a visibly transparent polymer matrix has recently emerged as a promising alternative approach to realize transparent display [1]. The localized surface plasmon resonance of these particles allows them to selectively scatter light at certain wavelengths. However, their performance is limited due to the inherent absorption in these plasmonic particles. In this study, we use finite element method to study scattering of light from titanium dioxide nanopillars. Due to the large refractive index contrast between the nanopillar and its surrounding medium, strong resonant scattering can be achieved across the entire visible spectrum by varying its dimensions. As a result of zero absorption and sharp resonances, the figure of merit of these structures for transparent display applications is found to exceed values previously reported for plasmonic nanoparticles. Furthermore, the angular distribution of light scattered from these structures can be tuned by varying their dimensions. These nanopillar structures may be used to create novel metasurfaces with applications in metalenses, see-through head-up displays, and smart glasses.
[1] C.W. Hsu et al., Nat. Commun. 5, 3152 (2014).