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arXiv · 1809.01949

Probing optical excitations in chevron-like armchair graphene nanoribbons

Richard Denk·Alberto Lodi-Rizzini·Shudong Wang·Michael Hohage·Peter Zeppenfeld·Jinming Cai·Roman Fasel·Pascal Ruffieux·Reinhard Berger·Z. Chen·Akimitsu Narita·Xiliang Feng·Klaus Muellen·Roberto Biagi·Valentina De Renzi·Deborah Prezzi·Alice Ruini·Andrea Ferretti
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Abstract

The bottom-up fabrication graphene nanoribbons (GNRs) has opened new opportunities to specifically control their electronic and optical properties by precisely controlling their atomic structure. Here, we address excitations in GNRs with periodic structural wiggles, so-called Chevron GNRs. Based on reflectance difference and high-resolution electron energy loss spectroscopies together with ab-initio simulations, we demonstrate that their excited-state properties are dominated by strongly bound excitons. The spectral fingerprints corresponding to different reaction stages in their bottom-up fabrication are also unequivocally identified, allowing us to follow the exciton build-up from the starting monomer precursor to the final ribbon structure.

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Richard Denk, Alberto Lodi-Rizzini, Shudong Wang, Michael Hohage, Peter Zeppenfeld, Jinming Cai, Roman Fasel, Pascal Ruffieux, Reinhard Berger, Z. Chen, Akimitsu Narita, Xiliang Feng, Klaus Muellen, Roberto Biagi, Valentina De Renzi, Deborah Prezzi, Alice Ruini, Andrea Ferretti. 2018-09-06. Probing optical excitations in chevron-like armchair graphene nanoribbons. https://doi.org/10.1039/c7nr06175g

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