V‐Shaped 3D Electrothermal Dual‐Function Metamaterials: Dynamic Dual‐Field Cloak Through Geometric Transformation

Multifunctional metamaterials have emerged as a transformative platform for controlling multi‐physical fields, promising applications in intelligent manufacturing, flexible electronics, thermal management, and energy conversion. However, conventional metamaterial designs typically prioritize optimizing single‐field responses, constraining their adaptability and functional integration potential in complex multi‐physics scenarios where coordinated regulation of multiple fields is required. Here, a V‐shaped 3D electrothermal dual‐function metamaterial (V‐ETDFM) architecture is proposed, enabling efficient and reconfigurable control of both electric and thermal transport. By expanding conduction pathways into 3D space, the proposed V‐shaped structure introduces additional degrees of freedom, enhancing its functional integration and adaptability. Through theoretical and numerical analysis, the feasibility of dynamically controlling cloak parameters, including size, shape, and spatial positioning, is demonstrated by reversibly stretching and compressing the V‐shaped framework based on transformation principles that maintain effective parameter invariance. Experimentally, a series of electrothermal cloaks with varying cloaked regions are fabricated to validate key design principles, confirming the static properties of the theoretical framework, while the implementation of real‐time dynamic tuning presents an avenue for future exploration. The work establishes a novel design strategy for electrothermal multifunctional metamaterials and provides a foundational theoretical framework for flexible and reconfigurable multi‐physics materials.