posted on 2020-04-24, 19:22authored byJonas Berzinš, Simonas Indrišiūnas, Koen van Erve, Arvind Nagarajan, Stefan Fasold, Michael Steinert, Giampiero Gerini, Paulius Gečys, Thomas Pertsch, Stefan M. B. Bäumer, Frank Setzpfandt
High-index
dielectric metasurfaces featuring Mie-type electric
and magnetic resonances have been of great interest in a variety of
applications such as imaging, sensing, photovoltaics, and others,
which led to the necessity of an efficient large-scale fabrication
technique. To address this, here we demonstrate the use of single-pulse
laser interference for direct patterning of an amorphous silicon film
into an array of Mie resonators a few hundred nanometers in diameter.
The proposed technique is based on laser-interference-induced dewetting.
A precise control of the laser pulse energy enables the fabrication
of ordered dielectric metasurfaces in areas spanning tens of micrometers
and consisting of thousands of hemispherical nanoparticles with a
single laser shot. The fabricated nanoparticles exhibit a wavelength-dependent
optical response with a strong electric dipole signature. Variation
of the predeposited silicon film thickness allows tailoring of the
resonances in the targeted visible and infrared spectral ranges. Such
direct and high-throughput fabrication is a step toward a simple realization
of spatially invariant metasurface-based devices.