Architectured materials
micromechanics modeling
Kirigami, the ancient art of paper cutting and folding to create three-dimensional structures, recently sheds new light on the three-dimensional nanofabrication techniques as it holds the key to building a large variety of micro-/nanostructures with unique and flexible functionalities. Compared with traditional 3D micro-/nanofabrication, kirigami and origami enable the shape transformation from 2D precursors to 3D architectures without the need of precise 3D translation in direct lithography or accurate alignment during indirect multilayer stacking. Benefiting from their unique transformation characteristics such as rotation and twisting, kirigami and origami greatly enrich the 3D geometries and complexities in the frontier of both fundamental sciences and practical applications, compared with those from conventional techniques. Using focused ion beam irradiation as our “atomic-scissors”, we introduce a one-step and on-site nano-kirigami method with nanoscale accuracy by in situ cutting and buckling a suspended gold film. By using the topography-guided stress equilibrium during global ion beam irradiation, versatile buckling, rotation, and twisting of nanostructures are simultaneously or selectively achieved. The exotic 3D structures are accurately controllable by programming ion doses, and well predictable by using an elastoplastic bilayer model.

A bilayer model of the stress distribution in gold nanofilm under global ion beam irradiation.


In designing architectured materials, our approach of combining mechanical modeling and fabrication constraints leads to the physical realization of a broad class of intricate structures which have demonstrated unprecedented mechanical, optical and acoustic properties (Liu et al., 2018) (Chen et al., 2021) (Liu et al., 2018) (Al-Ketan et al., 2018) (Surjadi et al., 2019) (Cushing* et al., 2021) (Shen et al., 2023).
References
2023
- Anisotropic Metallic Microlattice Structures for Underwater OperationsAdvanced Engineering Materials, 2023
2021
- Electromechanically reconfigurable optical nano-kirigamiNature communications, 2021
- Characterization of an underwater metamaterial made of aluminum honeycomb panels at low frequenciesThe Journal of the Acoustical Society of America, 2021
2019
- Mechanical metamaterials and their engineering applicationsAdvanced Engineering Materials, 2019
2018
- Nano-kirigami with giant optical chiralityScience advances, 2018
- Invited Article: Nano-kirigami metasurfaces by focused-ion-beam induced close-loop transformationApl Photonics, 2018
- Microarchitected stretching-dominated mechanical metamaterials with minimal surface topologiesAdvanced Engineering Materials, 2018