Systematic Parameter‐Space Mapping Strategy for a Deep‐Subwavelength‐Thick Low‐Frequency Electromagnetic Metasurface Absorber

ABSTRACT Overcoming the intrinsic thickness–frequency trade‐off while simultaneously ensuring ultra‐thinness, wide‐angle absorption, and mechanical conformability remains a fundamental challenge in designing electromagnetic (EM) absorbers for next‐generation integrated systems. Here, we propose a systematic parameter‐space mapping strategy that transcends conventional empirical optimization by establishing an explicit, continuous correlation between multi‐dimensional geometric parameters and absorption performance via large‐scale parametric sampling and multivariate regression. This approach enables the design of a deep‐subwavelength metasurface absorber with a record relative thickness of only 1/1573 (≈0.908 mm), achieving near‐perfect absorption of 98.7% at 0.21 GHz. The absorber further exhibits robust polarization insensitivity, outstanding angular stability up to 60° incidence, and excellent mechanical flexibility—retaining over 95% absorption efficiency under bending radii below 20 cm. Through synergistic integration of LC–RCL hybrid resonance, sine‐gap hexagonal topology, and a tunable air–dielectric–metal stack, the proposed architecture not only addresses the long‐standing thickness–frequency dilemma but also establishes a generalizable and efficient optimization paradigm for ultrathin, conformal, and wideband EM absorbers. This work paves the way for advanced applications in stealth technology, wearable electronics, and compact wireless communication systems.