Metamaterials as artificially structural materials exhibit customized properties unattainable in nature. While dynamic response is highly desired, metamaterials are usually passive and cannot be tuned post-fabrication. A conventional active metamaterial consists of rigid resonators mounted on flexible substrates that permit a limited amount of mechanical tuning. Given that rigid resonators permanently deform or debond under large strains (above 30%), the range of flexibility that is possible with tunable metamaterials is limited. Here, we propose a kirigami-inspired geometry that overcomes this limitation. The proposed design enhances stretchability exceeding 100% when compared with the existing design. A high degree of flexibility is achieved through “stress engineering” at the interface between rigid resonators and flexible substrates. Our design shows that the resonance modes shift at a rate of 3.32 ± 0.1 nm for every 1% change in strain, which is the highest tunability reported thus far. We demonstrate how this new concept can be applied to structural color. Using a single design, we demonstrated the full range of colors for the first time. The novel concept of highly stretchable metamaterials may revolutionize the field and enable its use in applications such as wearable sensors, smart displays, and switchable devices requiring extremely dynamic properties.

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Hybrid metasurfaces are made of metals and dielectrics in which dielectrics (metals) are sandwiched between metals (dielectrics) to control the reflection and transmission of light. The existing designs have low sensitivity, little color coverage, and a lack of flexibility. Here, a new structural color design is proposed in which metals and dielectric resonators are arranged spatially in 2D to form a lateral hybrid system, instead of being placed as layers. Such a design exhibits a high level of sensitivity to mechanical forces because it works via 2D optical coupling and light confinement between adjacent resonators. Our study shows that in-planar coupling of two dissimilar resonators can enhance sensitivity by an order of magnitude in comparison to stacking them. Metasurfaces with our design would have unprecedented mechanical tunability without compromising either the materials choice or processing. Using the proposed hybrid system, we demonstrate large tunability across the full range of colors with only a 10% change in the size of the lattice, which further proves its superiority over existing designs. This concept could find application in wearable devices that require high sensitivity to small mechanical fluctuations.