Researchers successfully control graphene nanoribbons using electrodes for the first time

August 16, 2023

Dübendorf/Beijing/Coventry - Researchers from the Swiss Federal Laboratories for Materials Science and Technology are examining quantum effects on graphene nanoribbons together with an international team. For the first time, the researchers have been able to attach electrodes to these nanoribbons and contact them.

An international team involving Empa researchers has, as part of a new study, for the first time succeeded in an attempt to control individual long and atomically precise graphene nanoribbons in an electroconductive manner. A ribbon of this kind measures in at just nine carbon atoms wide and a single nanometer in width, further details of which can be found in an Empa press release.

In order to contact individual ribbons, the researchers relied on electrodes of a similar size: They used carbon nanotubes that were also only a single nanometer in diameter. Access to high quality infrastructure at the Binning and Roher Nanotechnology Center, which is jointly operated by the Swiss Federal Institute of Technology in Zurich (ETH) and IBM Research Zurich in Rüschlikon in the canton of Zurich, was vital to testing and implementing this technology.

According to Empa, interdisciplinarity is the key to all of this: The researchers obtained the graphene nanoribbons from the Empa laboratory nanotech@surfaces. The precursor molecules were sourced from the Max Planck Institute for Polymer Research, which is based in the German city of Mainz. Members of the Transport at Nanoscale Interfaces lab at Empa integrated the nanoribbons in nanofabricated devices. The precisely aligned and high-quality carbon nanotubes required for this study were manufactured by a research group at Peking University in the Chinese capital Beijing, while computer science experts from the University of Warwick in the UK helped to interpret the study findings.

The researchers will now turn their attention to attempting to control different quantum states on a single nanoribbon and connecting two nanoribbons in series to form what is known as a double quantum dot. This could serve as a qubit, the smallest unit of information in a quantum computer, the press release explains. Potential use cases in connection with quantum switching, quantum sensing, and quantum energy conversion are also conceivable. ce/mm