Electrically Controlled Bimetallic Junctions for Atomic-Scale Electronics

Forming atomic-scalecontacts with attractive geometries and materialcompositions is a long-term goal of nanotechnology. Here, we showthat a rich family of bimetallic atomic-contacts can be fabricatedin break-junction setups. The structure and material composition ofthese contacts can be controlled by atomically precise electromigration,where the metal types of the electron-injecting and sink electrodesdetermine the type of atoms added to, or subtracted from, the contactstructure. The formed bimetallic structures include, for example,platinum and aluminum electrodes bridged by an atomic chain composedof platinum and aluminum atoms as well as iron-nickel single-atomcontacts that act as a spin-valve break junction without the needfor sophisticated spin-valve geometries. The versatile nature of atomiccontacts in bimetallic junctions and the ability to control theirstructure by electromigration can be used to expand the structuralvariety of atomic and molecular junctions and their span of properties.

Automated summary

In this study, a diverse family of bimetallic atomic contacts is demonstrated to be fabricated in break-junction setups, and the structure and material composition of these contacts can be controlled by atomically precise electromigration. The versatile nature of atomic contacts in bimetallic junctions and the ability to control their structure by electromigration can be used to expand the structural variety and property range of atomic and molecular junctions.