Wide-Angle Infrared Polarization Camouflage via Metallic Pillar Metasurfaces

Thermal radiation from conventional planar metals exhibits strong angle-dependent polarization splitting originated from intrinsic pseudo-Brewster effect. This creates a significant vulnerability for infrared camouflage against polarimetric detection, particularly at highly oblique observation angles. In this work, we demonstrate a wide-angle infrared polarization camouflage strategy utilizing a metallic pillar metasurface. By leveraging the boundary conditions imposed by the metallic pillar, the absorption of transverse magnetic (TM) waves driven by the vertical electric field component is suppressed across the long-wave infrared (LWIR) band. Consequently, our fabricated sample maintains high reflectivity for both polarization states, demonstrating a consistently low emissivity with degree of linear polarization (DoLP) limited to 2.3%, even at an extreme grazing angle of 80°. This robust and non-resonant design overcomes the angular dispersion limitations of macroscopic bulk materials and establishes a highly versatile paradigm for multidimensional thermal signature management.