Rolled 2D Heterostructures Could Lead To Miniaturized Electronics In The Future

Researchers at Penn State have created a type of heterostructure by layering two-dimensional materials atom thick. Researchers on the project believe the recent synthesis of the one-dimensional van der Waals heterostructures could lead to new miniaturized electronics not currently possible. The Penn State researchers were assisted on the project by a group of researchers from the University of Tokyo.

Heterostructures are commonly produced in engineering to create device properties not available using a single material. A van der Waals heterostructure is made up of 2D materials stacked directly on top of each other similar to Lego bricks. The material is held together using van der Waals force, an attractive force between uncharged molecules or atoms.

The heterostructures created by the researchers are different from those produced by engineers previously. Penn State researcher Slava V. Rotkin says the researchers created something that looks like a stack of 2D materials rolled into a perfect cylinder. Rotkin notes that the heterostructure is very compact, like a long sushi roll or hot dog. By using that method, the 2D-materials contact each other in the desired vertical heterostructure sequence without having to worry about lateral edges. That is described as a critical sequence for making super-small devices.

The team's creation is called hetero-nanotubes. Team researchers from the University of Tokyo recently fabricated electrodes on a hetero-nanotube and showed it could work as a tiny diode with high-performance for its size. Diodes are commonly used in optoelectronics, particularly in the core of photodetectors, solar cells, light-emitting devices, and more.

Rotkin notes that one particularly challenging task for the project was to ensure the one-dimensional van der Waals heterostructure cylinder had all the required material layers. The researchers believe their design opens the potential for a new class of materials for miniaturized electronics. In the future, Rotkin plans to extend the research to other materials.