A review of circuit analog absorbers: material synthesis, processing strategies, and electromagnetic applications

Alireza Bayat; Reza Mirzakhani; Pouria Dianati Souha

doi:10.53063/synsint.2026.61330

Alireza Bayat ¹
Reza Mirzakhani ¹
Pouria Dianati Souha ²

¹ Faculty of Technical and Engineering, Electrical Engineering-Telecommunication, Imam Khomeini International University, Qazvin, Iran
² Department of Aeronautical Engineering, Faculty of Aviation and Space Science, University of Kyrenia, Kyrenia, Mersin 10, Turkey

https://doi.org/10.53063/synsint.2026.61330

Abstract

Circuit analog absorbers (CAAs) represent a class of engineered functional materials designed for efficient electromagnetic wave attenuation through impedance matching and resonance-based mechanisms. While traditionally analyzed using electromagnetic circuit models, their practical realization critically depends on material synthesis strategies, microstructural engineering, and controlled fabrication processes. This review presents a comprehensive overview of CAAs from both electromagnetic and materials science perspectives, covering the evolution from classical absorber configurations to modern frequency selective surface (FSS) and metamaterial-based designs. Particular emphasis is placed on the synthesis of conductive and resistive materials, including carbon-based polymer composites, nanoparticle-derived metallic films, and multifunctional hybrid systems. The role of additive manufacturing, multilayer lamination, thermal consolidation, and low-temperature sintering in controlling electrical conductivity, dielectric response, and surface impedance is critically analyzed. Processing–structure–property relationships governing broadband absorption, polarization stability, and angular performance are discussed in the context of thermodynamic and kinetic phenomena including percolation network formation, polymer curing reactions, and nanoparticle sintering mechanisms. By integrating synthesis science with electromagnetic modeling, this review highlights how advanced fabrication routes and material engineering enable the development of thin, broadband, and mechanically robust absorbers suitable for radar cross-section reduction, electromagnetic interference shielding, and next-generation communication systems. The presented analysis provides a synthesis-oriented framework for future research on high-performance absorber materials and advanced sintering-driven fabrication strategies.

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Keywords: Circuit analog absorbers, Frequency selective surfaces (FSS), Metamaterial absorbers, Material synthesis, Additive manufacturing, Electromagnetic wave absorption

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