Multiband tunable thermal camouflage compatible with laser camouflage based on GST plasmonic metamaterial

Abstract

Abstract In this paper, we propose a simple plasmonic structure based on Ge2Sb2Te5 (GST) to realize tunable multiband camouflage and radiation heat dissipation. In the mid-infrared (MIR) (3–5 μm) range, the proposed structure has average emissivity of 0.18 ∼ 0.76 and can be applied in tunable thermal camouflage as the GST’s crystallization fraction increases from 0 to 1. In the 5–8 μm (safe window) range, radiation heat dissipation of the proposed structure may guarantee thermal stability of the system. In the long-infrared (8–14 μm) range, the designed emitter maintains a relatively stable and low average emissivity of 0.13 ∼ 0.19 when the crystallization fraction of GST changes from 0 to 1. In addition, due to surface lattice resonance of plasmonic metamaterial, our designed emitter can also achieve laser radar camouflage at the wavelength of 10.6 μm. We have also analyzed the dependence of the camouflage performance on the GST’s crystallization fractions, polarization angle and incident angle. Moreover, simulated thermal images demonstrate tunable thermal camouflage for various background temperatures and different ambient backgrounds in the MIR ranges.