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arXiv · 1811.07576

Full-scale Simulation of Electron Transport in Nanoporous Graphene: Probing the Talbot Effect

Gaetano Calogero·Nick R. Papior·Bernhard Kretz·Aran Garcia-Lekue·Thomas Frederiksen·Mads Brandbyge
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Abstract

Designing platforms to control phase-coherence and interference of electron waves is a cornerstone for future quantum electronics, computing or sensing. Nanoporous graphene (NPG) consisting of linked graphene nanoribbons has recently been fabricated using molecular precursors and bottom-up assembly [Moreno et al., Science 360, 199 (2018)] opening an avenue for controlling the electronic current in a two-dimensional material. By simulating electron transport in real-sized NPG samples we predict that electron waves injected from the tip of a scanning tunneling microscope (STM) behave similarly to photons in coupled waveguides, displaying a Talbot interference pattern. We link the origins of this effect to the band structure of the NPG and further demonstrate how this pattern may be mapped out by a second STM probe. We enable atomistic parameter-free calculations beyond the 100 nm scale by developing a new multi-scale method where first-principles density functional theory regions are seamlessly embedded into a large-scale tight-binding.

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Gaetano Calogero, Nick R. Papior, Bernhard Kretz, Aran Garcia-Lekue, Thomas Frederiksen, Mads Brandbyge. 2018-11-19. Full-scale Simulation of Electron Transport in Nanoporous Graphene: Probing the Talbot Effect. https://doi.org/10.1021/acs.nanolett.8b04616

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