Graphene origami enables easier access to exotic material states

Depending on the number of layers, their orientations, and their twist angle, twisted few-layer graphene (tFLG) is an ideal system for creating a variety of quantum states, such as superconductivity and magnetism. These materials are typically created by stacking and twisting individual sheets of graphene, an imperfect process in which separated layers are easily perturbed and can change configurations, which poses a structural challenge for achieving the desired states.

To address this challenge, Zou et al. developed an origami-based method for creating tFLGs. Their technique can generate various stacking and twisting configurations from a single sample with high controllability and stability at low cost.

Using a microtip consisting of a polymer dome with a micrometer-scale graphite tip, the researchers demonstrated an efficient way to fold and twist graphene. They placed graphene sheets on a silicon dioxide surface and moved the tip from the surface across the sheets to drag the sheets into the desired configurations.

They demonstrated a variety of layer numbers, configurations, and twist angles with this technique, including twisted bilayers, double bilayers, and double trilayers, as well as twisted ABC-stacked configurations. The samples remained strong against mechanical perturbations, like transferring, and thermally stable, possibly due to the robust structure created by the folded boundary connecting the layers.

The group hopes their microtip origami technique will inspire nanofabrication applications, such as for 2D transistors. They plan to continue optimizing their method for more precise twist angle and sample size control.

“We look forward to this technique being applied to construct other twisted few-layer 2D materials, such as twisted few-layer transition metal dichalcogenides and twisted few-layer hexagonal boron nitride, which may exhibit similar high structural robustness,” said author Long-Jing Yin.

Source: “Micro-tip manipulated origami for robust twisted few-layer graphene,” by Ruo-Jue Zou, Long Deng, Si-Min Xue, Feng-Fei Cai, Ling-Hui Tong, Yang Zhang, Yuan Tian, Li Zhang, Lijie Zhang, Zhihui Qin, and Long-Jing Yin, Applied Physics Letters (2025). The article can be accessed at https://doi.org/10.1063/5.0265918 .