Table 7 Dielectric materials: permittivity, conductivity, and performance22,23.
From: A high-performance ultra-compact plasmonic metamaterial structure for optical THz absorption
Material | Loss tangent | Refractive index (\(\eta\)) | Permittivity (ε) | Remarks |
|---|---|---|---|---|
SiO2 (Silicon Dioxide) | 0.0004 | ~ 1.45 | ~ 3.9 | Broad absorption, high transparency in the optical range. |
Al2O3 (Alumina) | 0.0001 | ~ 1.77 | ~ 9.4 | Low loss, high dielectric strength, high reflection. |
Si3N4 (Silicon Nitride) | 0.001 | ~ 2.0 | ~ 7.5 | High dielectric strength high reflection. |
GaAs (Gallium Arsenide) | 0.001 | ~ 3.66 | 13.1 | High electron mobility, significant reflection in lower THz region |
Mica | 0.0005 | ~ 1.6–1.7 | ~ 5–8 | Flat reflection response |
Porcelain | 0.002 | ~ 1.5 | ~ 5–7 | High dielectric strength, wide bandwidth but lesser than SiO2. |
