Printable Nanoscopic Metamaterial Absorbers and Images with Diffraction-Limited Resolution.
The fabrication of functional metamaterials with extreme feature resolution finds a host of applications such as the broad area of surface/light interaction. Nonplanar features of such structures can significantly enhance their performance and tunability, but their facile generation remains a challenge. Here, we show that carefully designed out-of-plane nanopillars made of metal-dielectric composites integrated in a metal-dielectric-nanocomposite configuration can absorb broadband light very effectively. We further demonstrate that electrohydrodynamic printing in a rapid nanodripping mode is able to generate precise out-of-plane forests of such composite nanopillars with deposition resolutions at the diffraction limit on flat and nonflat substrates. The nanocomposite nature of the printed material allows the fine-tuning of the overall visible light absorption from complete absorption to complete reflection by simply tuning the pillar height. Almost perfect absorption (∼95%) over the entire visible spectrum is achieved by a nanopillar forest covering only 6% of the printed area. Adjusting the height of individual pillar groups by design, we demonstrate on-demand control of the gray scale of a micrograph with a spatial resolution of 400 nm. These results constitute a significant step forward in ultrahigh resolution facile fabrication of out-of-plane nanostructures, important to a broad palette of light design applications.
Laboratory for Thermodynamics in Emerging Technologies, ETH Zurich , Sonneggstrasse 3, 8092 Zurich, Switzerland.
Patrizia
P
Richner
Laboratory for Thermodynamics in Emerging Technologies, ETH Zurich , Sonneggstrasse 3, 8092 Zurich, Switzerland.
Hadi
H
Eghlidi
Optical Materials Engineering Laboratory, ETH Zurich , Leonhardstrasse 21, 8092 Zurich, Switzerland.
Stephan J P
SJ
Kress
Laboratory for Thermodynamics in Emerging Technologies, ETH Zurich , Sonneggstrasse 3, 8092 Zurich, Switzerland.
Martin
M
Schmid
Optical Materials Engineering Laboratory, ETH Zurich , Leonhardstrasse 21, 8092 Zurich, Switzerland.
David J
DJ
Norris
Laboratory for Thermodynamics in Emerging Technologies, ETH Zurich , Sonneggstrasse 3, 8092 Zurich, Switzerland.
Dimos
D
Poulikakos
electrohydrodynamic NanoDrip printing; gold nanoparticle dispersion; high resolution printing; metamaterial; plasmonic absorber