That is the scanning electron microscope image of 3D plasmonic nanoantenna arrays. Eight metal-dielectric bilayer microbeams were modified with nanoslot-antenna array which supports localized surface plasmon resonances at desired wavelengths (near-infrared for this particular sample). After the sacrificial silicon underneath was etched away, The microbeams curled up due to the stress in the bilayer thinfilm, forming a “micro flower” which is sensitive to incident near-infrared light from all directions.
Such resonances can convert photons into phonons majorly through electron relaxation in the metal. Resulted temperature increase would cause the microbeams to deform slightly. This is visually like a swaying flower in breeze.
Hai (Justin) Zhu
Department of Materials Science & Engineering
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