Elementary phenomena in hybrid graphene nanoribbons on surfaces

Resumen del trabajo presentado al Symposium on Surface Science (3S), celebrado en St. Christoph am Arlberg (Austria) del 25 de febrero al 10 de marzo de 2018.Large aromatic carbon nanostructures are cornerstone materials due to their increasingly role in functional devices, but their synthesis in solution encounters size and shape limitations. Recently, it has been shown that the production of large graphenoid nanostructures with atomic precision can be realized on a metal surface using strategies of on-surface chemistry. Chemical routes have been established allowing us to steer synthesis by properly selecting the shape of organic precursors and produce large molecular platforms with tunable intrinsic properties such as the electronic band-gap, its magnetic behavior, or its reactivity. In this presentation, I will summarize results regarding the production of graphene nanoribbons and other carbon nanostructures with interesting electronic phenomenology. We combine high resolution STM imaging with local spectroscopy to unveil the success of a reaction pathway and to explore the effect of precursor shape and composition in electronic functionality of the ribbon. I will show that these ribbons behave as one-dimensional semiconductors and their band structure can be tuned by modifying their width. Doping can be introduced by incorporating additional species (see image of a high resolution GNR doped with CN groups). Furthermore, we developed a method to create quantum dots embedded in hybrid graphene nanoribbon. We found that ribbon bands are confined in them selectively, according to their symmetry. Quantum states can also be localized in extended flat platforms with cavities holding confined states. Finally, I will show that it is possible to incorporate magnetic molecular species bound to a ribbon. We show that the molecular spin survives in the ribbon by using spinexcitation inelastic spectroscopy.Peer reviewe