Selective and tunable thermal emission in metamaterials composed of oriented polar inclusions

We numerically investigated the peculiar spectral properties in the mid- to long-infrared range of a metamaterial composed of silicon carbide subwavelength oriented wires, deposited onto a silicon substrate. We show how anisotropic ellipsoids can be arranged, choosing both shape and orientation, so that the final resulting emissivity could match the emissivity peaks of hazardous chemicals for different polarizations of the emitted light. As an example, we design a metamaterial-based device that matches the emissivity lines of two explosives, such as XRD (cyclotrimethylenetrinitramine) and TNT (trinitrotoluene), providing a double check in polarization that could increase accuracy and versatility of chemical and biological sensors.