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Farmageddon: food and the culture of biotechnology
Kneen, Brewster. Farmageddon: food and the culture of biotechnology. Gabriola Island, BC: New Society, 1999
Brewster quasi bound states in the continuum in all-dielectric metasurfaces from single magnetic-dipole resonance meta-atoms
Bound states in the continuum (BICs) are ubiquitous in many areas of physics,
attracting especial interest for their ability to confine waves with infinite
lifetimes. Metasurfaces provide a suitable platform to realize them in
photonics; such BICs are remarkably robust, being however complex to tune in
frequency-wavevector space.Here we propose a scheme to engineer BICs and
quasi-BICs with single magnetic-dipole resonance meta-atoms. Upon changing the
orientation of the magnetic-dipole resonances, we show that the resulting
quasi-BICs,emerging from the symmetry-protected BIC at normal incidence, become
transparent for plane-wave illumination exactly at the magnetic-dipole angle,
due to a Brewster-like effect. While yielding infinite Q-factors at
normalincidence(canonical BIC), these are termed Brewster quasi-BICs since a
transmission channel is always allowed that slightly widens resonances at
oblique incidences. This is demonstrated experimentally through reflectance
measurements in the microwave regime with high-refractive-index mm-disk
metasurfaces. Such Brewster-inspired configuration is a plausible scenario to
achieve quasi-BICs throughout the electromagnetic spectrum inaccessible through
plane-wave illumination at given angles, which could be extrapolated to other
kind of waves.Comment: 15 pages, 7 figures; typos corrected, Figs. 3 & 5 modified, new Fig.
7 & references adde
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