Controlling the directionality of emitted far-field thermal radiation is a fundamental challenge in contemporary photonics and materials research. While photonic strategies have enabled angular selectivity emission over narrow sets bandwidths, inherently broadband phenomenon. We currently lack ability to constrain arbitrary ranges broad bandwidths. Here, we introduce experimentally realize grad...

Thermal emitters play a key role in controlling the thermal radiation emitted thermophotovoltaic systems and increasing their energy conversion efficiency. Here, we present different designs of with spectrally selective properties, based on easy-to-fabricate multilayer structures characterized by sharp transition from high to low emissivity region interest. Those make use refractory materials a...