Scientists from CIC nanoGUNE, Donostia International Physics Center (DIPC), Materials Physics Center (CFM) and CiQUS (Center for Research on Biological Chemistry and Molecular Materials), Spain, have created the tiniest magnetic device contacted, using graphene nanoribbons.
A single molecule can behave as the smallest electronic component of an electronic system. With this premise in mind, in recent years researchers in the field of molecular electronics have endeavoured to develop new approaches that bring closer the long-awaited objective of using molecules as electronic logic components. One of the most recent steps forward is appearing today in peer-reviewed journal Science Advances as a result of a new collaboration. This breakthrough has allowed contacting a single-molecule magnetic device for the first time using graphene nanoribbons.
Professor Nacho Pascual, leader of the Nanoimaging Group at nanoGUNE, said: “The idea is fascinating: to store information into a single molecule and read it.”
“We have known for long time how to make the molecules, but we could never wire them into a circuit until now”, he adds.
To achieve this goal, scientists developed graphene nanoribbons with the aim of using them as electrical wires; in addition, they also designed a method to precisely contact the molecule at predefined places.
What are graphene nanoribbons?
- Graphene nanoribbons (GNRs, also known as nano-graphite ribbons) are strips of graphene with a width of less than 50nm; and
- The one-dimensional nature of GNRs results in additional advantages over graphene sheets, the more widely known two-dimensional counterpart to GNRs.
Regarding the molecule creation process, the researchers have employed a chemical method based on guided chemical reactions over a metallic surface. CiQUS team leader, Diego Peña, said: “we designed and synthetised the building blocks with ‘glue-like’ chemical terminations at the points where contacts are to be created; from then on, nature does the rest of the job for us.”
The authors demonstrated the working function of the molecular device using scanning tunnelling microscopy (STM), a very advanced method to visualise atoms and molecules, and to measure their behaviour. By means of this tool, they could confirm under which conditions the magnetic information stored in the molecule could survive to the contact, opening a new way to develop novel materials for efficient electronics.
The work has been realised in the framework of a Spanish collaborative research consortium named FunMolDev (acronym of Functional Molecular Devices), funded by the Spanish Ministry for the Economy and Competitiveness, the Government of the Basque Autonomous Community, the Xunta de Galicia, and the European Union (EU).