The 112th AMCP Open Seminar

November 17 (Fri) 2017, 11:00-12:00

National Institute for Materials Science (NIMS)
Sengen Main Bldg. 8F Middle Seminar Room  → access

Pre-registration is not required.
For inquiries, please contact the Administrative Office.
This lecture is open to the public. Your participation is strongly encouraged.

Jose Ignacio Pascual, Professor (CIC nanoGUNE)

Elementary phenomena in hybrid graphene nanoribbons on metal surfaces

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 [1]. 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.
Our group is involved in a fruitful and Spanish-wide research project to advance in this field and create hybrid carbon-based molecular platforms with functional electronic, optical and magnetic properties. We use scanning tunneling microscope to explore the effect of adjusting the shape and composition of the molecular precursors in the production of graphene nanoribbons. Combining high resolution imaging (Fig. 1) with local spectroscopy, we unveil the success of a reaction pathway and correlate the result with their electronic functionality.
In this presentation, I will summarize our latest results regarding the production of graphene nanoribbons and other carbon nanostructures with interesting electronic phenomenology. 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 [1].
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 [2]. 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 spin-excitation inelastic spectroscopy.
REFERENCES

1. E.Carbonell et al. ACS Nano 11, 7355 (2017)
2. E.Carbonell, et al. Nano Letters 17, 50 (2017)