Electronic Transport in Twisted Nanoporous Graphene/Graphene Van Der Waals Heterostructures

Nanoporous graphene (NPG) is a promising candidate for the development of next generation electronic devices [1]. Recent advances in bottom-up on-surface chemistry have allowed the fabrication of increasingly large atomically precise samples of various NPG geometries, which can be thought as lateral arrays of weakly coupled semiconducting graphene nanoribbons [1,2]. Besides, the highly anisotropic electronic structure of NPG causes injected currents to flow according to the so-called Talbot effect interference pattern [3]. Such phase coherent phenomenon can be tuned by the introduction of structural and chemical modifications, making this 2D material appealing to control currents at the nanoscale [2,4]. On the other hand, van der Waals heterostructures have attracted great interest in the last decade due to their unconventional electronic properties and the high level of control achieved in the stacking of 2D materials. In this regard, the stacking of NPG over graphene has emerged as a noteworthy strategy to tune the electronic and transport properties of the latter [5,6]. However, the potential control of nanoscale currents in such heterostructure remains largely unexplored.<br/><br/>In this work, we theoretically study the electronic anisotropy and transport properties of twisted NPG/graphene van der Waals heterostructures. Combining Non-Equilibrium Green’s Functions with a tight-binding approach, we model devices comprising ~200,000 atoms and lengths over 50nm. In particular, we simulate the current flow in various commensurate and incommensurate geometries corresponding to different interlayer twist angles. The response of currents to the twist angle parameter is rationalize by means of the evolving interlayer coupling. Our findings showcase the versatility of NPG/graphene heterostructures for electronic applications and open new prospects for the realization of carbon nanocircuitry.<br/><br/>[1] C. Moreno et al., Science 360, 199 (2018)<br/>[2] C. Moreno, X. Diaz de Cerio et al., J. Am. Chem. Soc. 145, 8988 (2023)<br/>[3] G. Calogero et al., Nano Lett. 19, 576 (2019)<br/>[4] I. Alcón et al., Adv. Funct. Mater., 2104031 (2021)<br/>[5] A. Antidormi and A. W. Cummings, AIP Advances 11, 115007 (2021)<br/>[6] B. Lee and J. Kang, Adv. Electron. Mater., 2200252 (2022)