Gratings and their quasistatic equivalents for high optical absorptance

Abstract

We consider thin lamellar and cylinder gratings, composed of silicon carbide and air, and investigate the conditions under which they can totally absorb an incident plane wave, for both p and s polarizations. We also consider thin-film equivalent in the quasistatic limit to the gratings, deriving the effective dielectric tensor for cylinder gratings. We show that the accuracy of the quasistatic models is a strong function of polarization, wavelength, and grating thickness due to the resonant nature of the optical constants of silicon carbide but that these models can be quantitatively accurate and give a good qualitative guide to the parameter values under which thin gratings can deliver high optical absorptance.

Theoretical study on the possible use of SiC microparticles as photothermal agents for the heating of bacteria

“…We note that it has been shown experimentally that the reflectivity of a periodically microstructured SiC surface can be reduced to near zero for wavelengths around 11 µm [58]. Recently a theoretical study on absorption of light in the SPhR regime by thin gratings composed of SiC and air studied conditions under which there can be high absorption [59]. At any rate, based on calculations in section 2 we make the following speculative estimates of heating of the roughened SiC surface.…”

Electromagnetic field quantization and quantum optical input-output relation for grating

“…Based on the dimension of the periodicity, they can be classified as one dimensional (1D) grating 2 and two dimensional variation of such structures. A lot of fundamental study on these structures has been conducted, including band structure 3–5 , scattering 6,7 , absorption 8,9 , nonlinear optical effects 10–12 , and so on. The extraordinary features, like guided resonance, light bound states in the continuum (BICs) 13–15 , and so on, enable these structure to be applied to many optical processes, for example, hollow-core waveguide 16 , high-Q resonators 17 , surface-normal coupler 18 , vertical-cavity surface-emitting lasers 19 , high-NA planar lenses 20 , surface-normal second-harmonic emission 21 , and so on.…”