Broadband Absorbers and Selective Emitters based on Plasmonic Brewster   Metasurfaces
  We discuss the possibility of realizing utlrabroadband omnidirectional absorbers and angularly selective coherent thermal emitters based on properly patterned plasmonic metastructures. Instead of relying on resonant concentration effects that inherently limit the bandwidth, we base our design on the combination of two inherently nonresonant effects: plasmonic Brewster funneling and adiabatic plasmonic focusing. With this approach, we demonstrate compact, broadband absorption and emission spanning terahertz, infrared and optical frequencies, ideal for various energy and defense applications. 
Christos Argyropoulos, Khai Q. Le, Nadia Mattiucci, Giuseppe   D'Aguanno, Andrea Alu
cond-mat.mes-hall cond-mat.mtrl-sci physics.optics