Strain Amplification Strategy for the Regulation of 2D and 3D Optical Micro/Nanostructures

Three-dimensional (3D) nanostructures have attracted significant attention due to their excellent properties in electromagnetic field localization and regulation, which are hardly obtained from the planar nanostructure. Recently, a promising approach, internal or external triggers induced by 2D precursor to 3D nanostructure transformation, has emerged to provide a solid basis for studying and applying 3D micro/nanostructures. However, the function and research of the constraint blocks in 2D precursors are still superficial, which restricts its development. Here, we have theoretically proposed and experimentally demonstrated a strain amplification strategy for dynamically regulating 2D and 3D optical micro/nanostructures. Arising from the restriction of the paired constraint blocks, the strain between the blocks is significantly increased to obtain a strain amplification effect, which can be simulated by a finite element method (FEM), and verified experimentally from the gap change between the 2D gratings. Meanwhile, such a strategy can regulate the 3D optical micro/nanostructures, such as the nanopyramids studied here. The results indicate that the strain increment depends on the design of the paired blocks, especially their length. Moreover, the reflection properties of a nanorod dimer array were dynamically regulated by a combination of prestretching. The proposed strain amplification strategy provides opportunities to regulate the 2D and 3D nanostructures for active optical components, flexible electronics, and integrated circuits.