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arXiv · 2302.08446

Engineering Robust Metallic Zero-Mode States in Olympicene Graphene Nanoribbons

Ryan D. McCurdy·Aidan Delgado·Jingwei Jiang·Junmian Zhu·Ethan Chi Ho Wen·Raymond E. Blackwell·Gregory C. Veber·Shenkai Wang·Steven G. Louie·Felix R. Fischer
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Abstract

Metallic graphene nanoribbons (GNRs) represent a critical component in the toolbox of low-dimensional functional materials technolo-gy serving as 1D interconnects capable of both electronic and quantum information transport. The structural constraints imposed by on-surface bottom-up GNR synthesis protocols along with the limited control over orientation and sequence of asymmetric monomer building blocks during the radical step-growth polymerization has plagued the design and assembly of metallic GNRs. Here we report the regioregular synthesis of GNRs hosting robust metallic states by embedding a symmetric zero-mode superlattice along the backbone of a GNR. Tight-binding electronic structure models predict a strong nearest-neighbor electron hopping interaction between adjacent zero-mode states resulting in a dispersive metallic band. First principles DFT-LDA calculations confirm this prediction and the robust, metallic zero-mode band of olympicene GNRs (oGNRs) is experimentally corroborated by scanning tunneling spectroscopy.

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Ryan D. McCurdy, Aidan Delgado, Jingwei Jiang, Junmian Zhu, Ethan Chi Ho Wen, Raymond E. Blackwell, Gregory C. Veber, Shenkai Wang, Steven G. Louie, Felix R. Fischer. 2023-02-16. Engineering Robust Metallic Zero-Mode States in Olympicene Graphene Nanoribbons. https://arxiv.org/abs/2302.08446

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