Passive core-shell-based metamaterials to control infrared emissions

The need to control thermal emissions when devices, such as infrared (IR) sensors, are in close proximity to a heat source, has a number of defense and security applications. By tuning the geometry and material properties of core-shell particles, we will illustrate how they can be designed to control IR emissions, i.e., electromagnetic waves in the 8–12 µm range. In particular, we will illustrate the realization of Huygens´ source types of nano- and micron-sized particles that have low backscattering and large forward scattering. Their integration into a substrate near to its interface leads to additional directionality control that has been investigated for practical applications.