Simultaneous single-peak and narrowband thermal emission enabled by hybrid metal-polar dielectric structures

Simultaneous single-peak and narrowband thermal emitters with the merits of a simple configuration and ease-of-fabrication provide a path to enhance the energy utilization efficiency while they remain a challenge. Here, we demonstrate simultaneous single-peak and narrowband thermal emission by hybridizing metal microstructures with polar dielectric substrates. The metal provides single-peak emission in a broad spectrum range and the polar dielectric assists narrowband operation. The measured peak emissivity of the single-peak transverse-magnetic-polarized emission is 0.94 with a quality factor of 19 at the wavelength of 11.2 μm, and the emission at all other wavelengths from 2.5 μm to 25 μm is significantly suppressed. The utilization of the refractory material (molybdenum) provides further possibility for such a device to operate at temperatures up to 600 °C. These simultaneous single-peak and narrowband thermal emitters suggest avenues for numerous energy-efficient applications including gas sensing, thermal sources, and thermophotovoltaics.