Ultra-Wideband Flexible Metamaterial Absorber Based on Silver Nanoparticle Using Inkjet Printing

A novel ultra-wideband (UWB) flexible metamaterial absorber (MA) is proposed and thoroughly examined both numerically and experimentally for microwave range applications. The design is based on a rectangular ring array of silver nanoparticles (SNP) inkjet-printed on an ultra-thin flexible Polyethylene terephthalate (PET) substrate. The finite integration technique (FIT) is employed to simulate the proposed design. The results demonstrate absorption performance surpassing 90% across a wide frequency span, ranging from 3 to 96.4 GHz, for both transverse electric (TE) and transverse magnetic (TM) polarizations under normal incidence. The surface current and electric field distributions at different frequencies reveal the underlying physical mechanisms responsible for the UWB absorption phenomenon. Perfect absorption is due to the intrinsic character of the metamaterial structure that can be confirmed from the extracted effective permittivity and effective permeability. The proposed design is fabricated and experimentally tested, demonstrating good agreement with the simulation outcomes. The metamaterial absorber's remarkable characteristics make it highly promising for various applications in communications and stealth, primarily due to its perfect absorptivity over the UWB frequency range.