Flat bands and electron correlations in graphene.

From the moment it was isolated as a 2D material, graphene has become a remarkable subject of research, exhibiting novel phenomena that extend to almost any domain within condensed matter physics and physical chemistry. Recently, this was further extended with the discovery of 'magic-angle graphene', in which twisted bilayer graphene (TBG) with nearly flat bands was observed to behave as a high-temperature superconductor - the Physics World 2018 Breakthrough of the Year. However, TBG remains extremely challenging to fabricate which, together with intrinsic constraints on tunability, limit further research on the electron correlation phenomena emerging from its flat bands. Here we propose to explore an alternative system, based on periodic lattices of strained nanobubbles in single-layer graphene, which host similar flat bands to those in TBG, with the advantage of being much more tunable (e.g. allowing for even flatter bands) and scalable (crucial for further fundamental studies as well as eventual applications). The fabrication is based on an original approach that combines ultra-low energy ion implantation (a unique technique developed by the consortium) and state-of-the-art nanofabrication. The tunability of the fabrication approach, together with the unique expertise of the consortium on theoretical tools for electronic structure calculations of such systems, will allow us to produce specific electron correlation phenomena (superconductivity and magnetism) by design.

Keywords:GRAPHENE

Disciplines:Electronic (transport) properties, Magnetism and superconductivity, Nanophysics and nanosystems, Semiconductors and semimetals, Surfaces, interfaces, 2D materials

Project type:Collaboration project