Optimized thermal emitters using
optical resonances have been attracting
increased attention for diverse applications, such as infrared (IR)
sensing, thermal imaging, gas sensing, thermophotovoltaics, thermal
camouflage, and radiative cooling. Depending on the applications,
the recently developed IR devices have been tailored to achieve not
only spectrally engineered emission but also spatially resolved emission
using various nanometallic structures, metamaterials, and multistacking
layers, which accompany high structural complexity and prohibitive
production cost. Herein, this article presents a simple and affordable
approach to obtain spatially and spectrally selective hybrid thermal
emitters (HTEs) based on spoof surface plasmons of microscaled Ag
grooves manifested in encapsulation polymer layers. Theoretical analyses
found that the polymer hybrid plasmonics allows diverse emission tuning
within the long-wave IR (LWIR; 8–14 μm) region as follows:
(1) spatially selective emission peaks only exist in the interface
of Ag grooves and IR-transparent layers and (2) near-unity spectrally
selective emission is obtained by refining inherent emissivity of
a thin IR-opaque layer. Also, parametric studies computationally optimized
the structural parameters for spatially and spectrally selective HTEs.
Using the optimized parameters, the authors fabricated two HTEs and
demonstrated the intriguing emission features in terms of infrared
data encoding/decoding and radiative cooling, respectively. These
successful demonstrations open up the applicability of HTEs for tailoring
IR emission in a spatially and spectrally selective manner.