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We propose a reconfigurable electromagnetic metamaterial device driven by magnetic fields. A field-driven reconfigurable metamaterial component (FD-RMC) consisting of periodic channels and compound liquid medium is fabricated. The transition of the electromagnetic metamaterial device from an absorbing state to a frequency-selective state is realized by placing the FD-RMC filled with a compound liquid medium in a gradient magnetic field. The effective bandwidth of the FD-RMC is 14.1 GHz (3.9–18 GHz) in the absorbing state, and it exhibits obvious filtering characteristics at 7.8 GHz in the frequency-selective state. Repeated testing showed that the FD-RMC has great repeatable reconfigurability.

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Thermal metamaterials have garnered significant attention for their potential to manipulate heat flow, leading to the development of various thermal metadevices such as thermal cloaks, concentrators, and rotators. However, the theoretical study of thermal metadevices with nonconformal geometry remains limited due to design and fabrication challenges. This letter proposes a method for designing and manufacturing nonconformal thermal metamaterials using the conformal discrete theory to simplify the anisotropic thermal conductivity tensors. The method involves 3D printing three thermal metadevices (a thermal cloak, concentrator, and rotator) with complex nonconformal geometry. Simulation and experimental results demonstrate the successful implementation of cloaking, concentrating, and rotating functionalities. Moreover, the thermal metadevices still maintained thermal functionality well under the condition of omnidirectional heat flow. This work provides guidance for the design and manufacture of nonconformal thermal metamaterials, as well as their potential applications in other fields such as electrics/magnetics, electromagnetics/optics, and acoustics.

Objects can be identified based on their distinctive scattering signatures in multiple physical areas such as optics, electromagnetics, and thermotics. To ensure comprehensive stealth and camouflage capabilities, antisense devices with multiphysical field coupling are highly desired. Herein, a multifunctional antisense metadevice that achieves stealth in the microwave band while also generating multiple camouflage images from the original object's position during the heat conduction process is proposed and demonstrated. The metadevice combines both antimicrowave detection and camouflage infrared imaging capabilities, resulting in broadband electromagnetic stealth and thermal camouflage effect. Experimental and simulation results confirm the metadevice's ability to achieve these multifunctional capabilities in temperature‐dependent cases. The development of such multifunctional devices that span physical fields provides new avenues for the design and preparation of multifunctional structures.