Thermal superscatterer: amplification of thermal scattering signatures for arbitrarily shaped thermal materials

TL;DR

This paper introduces a thermal superscatterer that amplifies the thermal scattering signature of small objects, enabling size-independent thermal signature manipulation with potential applications in thermal camouflage and energy management.

Contribution

The work extends superscattering concepts to thermal fields using transformation thermodynamics and engineered negative-conductivity shells, demonstrating practical fabrication and experimental validation.

Findings

Amplifies thermal scattering signature ninefold

Mimics larger or transformed thermal scatterers

Potential for thermal camouflage and energy control

Abstract

The concept of superscattering is extended to the thermal field through the design of a thermal superscatterer based on transformation thermodynamics. A small thermal scatterer of arbitrary shape and conductivity is encapsulated with an engineered negative-conductivity shell, creating a composite that mimics the scattering signature of a significantly larger scatterer. The amplified signature can match either a conformal larger scatterer (preserving conductivity) or a geometry-transformed one (modified conductivity). The implementation employs a positive-conductivity shell integrated with active thermal metasurfaces, demonstrated through three representative examples: super-insulating thermal scattering, super-conducting thermal scattering, and equivalent thermally transparent effects. Experimental validation shows the fabricated superscatterer amplifies the thermal scattering signature of a small insulated circular region by nine times, effectively mimicking the scattering signature of a circular region with ninefold radius. This approach enables thermal signature manipulation beyond physical size constraints, with potential applications in thermal superabsorbers/supersources, thermal camouflage, and energy management.