Ultra-Thin and Broadband P-Band Metamaterial Absorber Based on Carbonyl Iron Powder Composites

• Published in: Materials Vol. 17; no. 5; p. 1157
• Main Authors: Zhou, Mengyu, Chen, Yubin, He, Yuguang, Yang, Cheng
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 01.03.2024; MDPI
• Subjects: Absorbers; Absorbers (materials); Absorption; Analysis; Aviation; Broadband; broadband absorption; Broadband transmission; Carbonyl powders; Design; Electric fields; electromagnetic parameters; Electromagnetism; Energy distribution; Genetic algorithms; Iron; Magnetic fields; metamaterial absorber; Metamaterials; Mutation; Optimization; P-band; Parameters; Particulate composites; Periodic structures; Permeability; Powders; Simulation; Substrates; Transmission lines; electromagnetic parameters; P-band; metamaterial absorber; broadband absorption
• ISSN: 1996-1944; 1996-1944
• DOI: 10.3390/ma17051157

The field of P-band (0.3-1 GHz) absorption has witnessed rapid development in metamaterial absorbers due to their exceptional designability and the absence of restrictions imposed by the one-fourth wavelength rule. In this study, we combined carbonyl iron powder (CIP) composites with a periodic structure composed of metal capacitive patterns and employed a genetic algorithm (GA) to optimize the electromagnetic parameters of the CIP substrate. By selecting the appropriate shape and material for the units of pattern based on transmission line theory, as well as regulating relevant structural parameters, we successfully designed an ultra-thin broadband metamaterial absorber for the P-band. Experimental results demonstrate that within the range of 0.3-0.85 GHz, the reflection loss of our absorber remains below -5 dB, with a maximum value of -9.54 dB occurring at 0.45 GHz. Remarkably, this absorber possesses a thickness equivalent to only 1/293 of its working wavelength. Then, we conducted analyses on electric field distribution, magnetic field distribution, and energy loss density. Our findings suggest that high-performance absorption in metamaterials can be attributed to λ/4 resonant or coupling effects between structural units or diffraction phenomena. This absorber offers several advantages, including broad low-frequency absorption capability, ultra-thin profile, and convenient fabrication process, thus providing valuable theoretical insights for designing metamaterial structures.