Self-Focused Thermal Emission and Holography Realized by Mesoscopic Thermal Emitters

Controlling thermal emission plays a vital role in various applications. Existing control of thermal emissions have been limited to simple functions such as directional and spectral selectivity. Complex control of thermal emission remains underexplored. Here, we show a new type of thermal emitters with mesoscopic structures. These emitters have sizes in the range of tens to hundreds of wavelengths. The wave effects of emitted thermal photons enable complex control of thermal emission through optical coupling. These emitters can exhibit phenomena such as self-focused emission and thermal holograph. A new theoretical framework is introduced to describe rich wave dynamics in mesoscopic thermal emitters. It accurately accounts for both the wave dynamics in electrically large structures and the statistical fluctuation of thermal emission.