Helix of carbon nanostructures for polarization loss enhancement under an electromagnetic field

Abstract

A thorough understanding of the interrelation between helical architectures and intrinsic electromagnetic characteristics in carbon nanostructures is essential for developing high-performance electromagnetic wave (EMW) absorbers. Here, a soft-template approach is employed to synthesize helical carbon structures with an identical degree of graphitization, defect densities, and chemical compositions for elucidating the EMW absorption loss mechanism. Different helical configurations can be obtained by regulating induced templates and simulated via the full-wave EM simulation method. The results demonstrate that the optimised helical geometry has achieved a remarkably effective absorption bandwidth of 7.44 GHz, which represents a 33% improvement compared to its linear counterparts, superior to the state-of-the-art powder carbon-based absorbers. Theoretical simulations have validated that the helical curvature induces an amplification of interfacial polarisation through geometric phase modulation. Concurrently, radar cross-section (RCS) analysis reveals exceptional wave-attenuation performance, achieving an ultra-low RCS value of −54 dB with 90% backscattering reduction, that are critical metrics for electromagnetic shielding structures and aerospace vehicle applications. This study clarifies the relationship between the helical configuration and polarisation loss mechanism, providing a new avenue for designing high-performance EMW absorption materials.