image: schematic diagram and function illustration of the proposed mcm and its magic cube supercell. MCM is formed by an array of supercells arranged in a square lattice of magic cube as a plinth. The reflective phase responses of each meta-particle are controlled by 3d permutations of sub-blocks directly below it and can be independently tuned over six levels. Under full-polarization incident electromagnetic waves, MCM can be mechanically and flexibly processed to realize customized functionalities, including but not limited to type-Ⅰ (reconfigurable achromatic metalens) and type-Ⅱ (tunable multifunctional beam generators) ranging from f1 to f4. the upper-middle panel exhibits the meta-particle with transparent substrate, allowing for real-time sequence mapping visually.
Credit: ©Science China Press
Artificial structural materials composed of subwavelength periodic or quasi-periodic elements, known as metamaterials, have garnered widespread attention and in-depth exploration in the scientific and engineering communities since their inception, offering the potential to achieve remarkable phenomena that are difficult or even impossible to achieve with traditional materials. To adapt to complex and dynamic environmental demands, dynamic metamaterials have been proposed, aiming to overcome the design limitations of static metamaterials by altering equivalent physical parameters or reconfiguring material morphology, typically corresponding to electrical or mechanical excitation, respectively. Mechanical tunable metamaterials, compared to electrically tunable metamaterials, though inferior in sensitivity and response speed, exhibit advantages in industrial manufacturing and extreme environments due to their simple structural composition and excellent mechanical load-bearing capacity. However, current mechanical control methods have only been validated in certain electromagnetic dynamic control applications and still face significant challenges, including polarization sensitivity, poor real-time feedback, and low information capacity, primarily due to the absence of effective deformation modes and design strategies.
To this end, Professor Wang's team and their collaborators pioneered the integration of a 3D magic cube architecture and metamaterial elements. This collaborative design framework successfully addressed the key limitations of existing mechanical control methods, which are characterized by low adaptability, weak interactivity, and limited information capacity. The results of this work have been published in Science Bulletin.
The research team bonded optically transparent metamaterial elements onto the magic cube sub-blocks, leveraging their symmetrically distributed spatial structure and the repetitive nature of the sub-blocks to independently control the position and orientation distribution of coplanar metamaterial elements, thereby constructing magic cube metamaterials (MCMs) with variable electromagnetic fields. Compared to classical origami/kirigami auxiliary frameworks, or mechanically programmable metamaterials, the spatial permutation of the third-order magic cube expands the amount of information they can carry and the degrees of freedom they can manipulate. By leveraging geometric transformations in mathematics, MCMs achieve functional integration and polarization adaptation in physics. Two proof-of-concept prototypes, including reconfigurable achromatic metalens and switchable multibeam generator, demonstrate that this design scheme exhibits high polarization adaptability, distinct identifiable states, and ease of deployment in switching between electromagnetic near- and far-field properties, paving the way for future human-machine interaction and electronic interference devices.
The research team emphasized the broader vision, stating, “This technology is merely our first step toward a new paradigm in dynamic metamaterial design. Looking ahead, we plan to advance the transformation and practical application of this metamaterial technology from the laboratory to diversified and systematic real-world applications through three key areas: mechatronic hybridization, intelligent integration, and spectrum compatibility.”
Journal
Science Bulletin