From Magnetoelectric Core–Shell Structure to Compound Eye‐Inspired Metamaterials: Multiscale Design of Ultra‐Wideband Electromagnetic Wave Absorber Device

Abstract The integration of macroscopic and microscopic structural designs plays a crucial role in developing high‐performance electromagnetic wave (EMW) absorber devices. In this work, an innovative metamaterial based on a multi‐scale design is introduced to address the challenge of narrowband absorption. Specifically, at the microscopic scale, a highly efficient absorbing material (FCIP@SiO 2 @Ppy) is synthesized through an integrated optimization strategy, in which functional layers are uniquely combined to maximize performance. By leveraging heterogeneous interfaces, this design establishes a magneto‐electric coupling network, ensuring excellent impedance matching and significantly enhancing the EMW absorption capacity of the material. Notably, the material achieves a record low reflection loss (RL) of −66.66 dB at 9.95 GHz with a broad absorption bandwidth of 5.92 GHz (RL ≤ −10 dB), which is subsequently used to fabricate metamaterial absorber device. Building upon this, at the macroscopic scale, inspired by the compound eye structure of arthropods, a groundbreaking metamaterial structure is proposed. Simulations reveal the achievement of ultra‐wideband absorption (2.75–18 GHz) with a remarkably thin thickness of just 12 mm. These pioneering results present effective strategies for the development of next‐generation high‐performance EMW absorber devices.